Mailchimp Multilingual Campaigns
What this skill covers
Campaign- and audience-level patterns for sending multilingual emails through Mailchimp. Two distinct shapes:
- Single list, multiple languages — one audience whose members speak different languages. The Belgian (NL/FR/DE), Swiss (DE/FR/IT/RM), Canadian (EN/FR), and Singaporean (EN/ZH/MS/TA) case. Use Mailchimp's audience-level
MC_LANGUAGE field plus conditional content (or segment routing).
- Global brand, multiple markets — separate audiences per market, sometimes separate Mailchimp accounts. Template syndication / forking workflow, per-market regulatory footers, multi-account orchestration. Bigger-org territory.
Template-level concerns are handled by the sibling skill mailchimp-template-language. That covers the lang attribute, character coverage, per-script font stacks, RTL layout, and everything inside a single template file. This skill adds the audience and campaign layer on top.
When to use this skill
Trigger this skill when:
- The user is sending a campaign to subscribers who speak different languages.
- The user asks about
*|MC_LANGUAGE|*, *|IF:MC_LANGUAGE=...|*, language segments, or per-language content blocks.
- The user is planning a multi-market send across separate audiences or Mailchimp accounts.
- The user asks "should I send one campaign with conditional content, or one campaign per language?"
- The user is in Belgium / Switzerland / Canada / Singapore / Luxembourg / South Africa / India / any market with multiple official languages and is sending email to all of them.
Do not use this skill for:
- A single-language Mailchimp template — load
mailchimp-template-language directly.
- Generic web/app i18n (not Mailchimp).
- Professional translation workflow tooling (this skill orchestrates Mailchimp's built-ins; it doesn't translate text).
The three documented paths
Mailchimp's own contact-languages doc (https://mailchimp.com/help/view-and-edit-contact-languages/) lists three sanctioned approaches for serving content in multiple languages. None is universally best — pick based on constraints.
| Path |
What it is |
Best for |
| Segments + separate campaigns |
Build a Mailchimp segment per language (filter on Language field), send a separate campaign to each segment. Each campaign has its own subject, preheader, from-name, send-time. |
When the subject line / preheader / from-name / send time must differ per language — which is most professional sends |
| Single campaign with conditional content |
One campaign, one subject, one send. Body uses *|IF:MC_LANGUAGE=xx|*…*|ELSE:|*…*|END:IF|* blocks to vary content per recipient. |
When the subject is universal (brand name, generic phrase) and only the body needs to switch. Lower ops cost; less subject-line flexibility |
| TRANSLATE link |
Same campaign for everyone, include *|TRANSLATE:xx|* to insert Google Translate links pointing at the campaign archive. Recipients self-serve. |
The lightweight option. Fine for low-stakes informational sends; not appropriate for branded marketing where translation quality matters |
The bright line: Mailchimp explicitly states "It's not possible to translate the subject line of your email." If the subject line must differ per language, you're on the segments path. There's no workaround.
Hard rules
Things that will silently break a multilingual campaign:
*|MC_LANGUAGE|* returns an ISO 639-1 code like en, fr, nl, de. Mailchimp accepts a small set of locale variants too: fr_CA, es_ES, pt_PT. Most variants you might expect — de_CH, it_CH, rm, zh_Hant — are not in Mailchimp's accepted list and collapse to the base code (or are absent entirely). See references/language-detection.md for the full accepted list.- Conditional comparisons are case-sensitive.
*|IF:MC_LANGUAGE=fr|* matches; *|IF:MC_LANGUAGE=FR|* does not. Use lowercase to match the ISO codes Mailchimp stores.
- Always provide a
*|ELSE:|* fallback. New subscribers default to "Not yet detected" until Mailchimp's auto-detection runs (or the user sets a value manually). Without an ELSE branch, those recipients get an empty email body. The fallback is usually the brand's primary language.
- A conditional block must open and close within the same
mc:edit region. Splitting *|IF:MC_LANGUAGE=fr|* across two editable regions silently breaks at send time. See mailchimp-template-language → references/merge-tags.md for the block-scope rule.
- Compliance footer must be present in every language version. Translate the text (Unsubscribe / Update preferences) but keep the merge tags as-is (
*|UNSUB|*, *|HTML:LIST_ADDRESS_HTML|*). Address and unsubscribe link are not optional in any locale.
- Language preference is a system-level field, not a custom merge field. Don't try to set it via
*|MERGE5|* or similar; use Mailchimp's built-in Language attribute (auto-detected from browser, exposed on signup forms, manageable via API and CSV import).
Workflow
When asked to plan or build a multilingual campaign, work through these phases. Each phase points to the reference file that owns the detail.
Phase 1 — Identify the shape
Single-list-multilingual (one audience, many languages) or multi-market-global-brand (multiple audiences, often multiple accounts)? Confirm with the user. The patterns and reference files differ.
For multi-market work, load references/multi-market.md.
For single-list-multilingual (the default and best-supported shape in Mailchimp), continue.
Phase 2 — Map the constraints
Ask the user — or infer from the brief:
- Which languages? Get the list and the priority (which is the "primary" / fallback).
- Must the subject line differ per language? If yes → segments path is forced. If no → conditional-content path is viable.
- How is language preference captured today? Browser auto-detection (Mailchimp's default), signup-form field, CSV import, or unset on all contacts? If unset, the user needs to set it before sending matters.
- Are there per-language regulatory differences? Different compliance footer text, currency, jurisdiction. Single-list-multilingual generally implies one jurisdiction (Belgium has one address); multi-market implies many.
Phase 3 — Choose the path
Load references/segments-vs-conditional.md to walk the decision tree and apply the choice to the user's constraints.
Phase 4 — Establish how language is captured
Load references/language-detection.md to confirm how MC_LANGUAGE gets populated and what values are allowed. If the user's audience has mostly "Not yet detected" contacts, this is the gate — language-aware sends only work once language is set on contacts.
Phase 5 — Build the template
Load mailchimp-template-language (the sibling skill) for the actual HTML scaffold, mc:edit placement, responsive structure, accessibility, and validation. This skill doesn't duplicate that work — it composes with it.
When the path requires conditional content blocks (single-campaign approach, or hybrid where some sections vary per language but the subject doesn't), load references/conditional-content.md for the *|IF:MC_LANGUAGE=...|* patterns: per-language hero, CTA, compliance footer, signature block.
Phase 6 — Validate
Two layers:
- Structural: run
mailchimp-template-language/scripts/validate.py on each template file. Same validator as the monolingual flow.
- Multilingual completeness — manual checklist:
- Every conditional block has an
*|ELSE:|* fallback for "Not yet detected" contacts.
- Every language's content path includes the compliance footer.
- The
lang attribute on <html> matches the dominant language of the template (for the segments path, set per-segment).
- Font stacks cover every script the languages need (see
mailchimp-template-language/references/typography.md).
Phase 7 — Test
Mailchimp's "Preview & Test → Enter preview mode" lets you fill merge tags with the data of a chosen subscriber. Preview against at least:
- A subscriber with
MC_LANGUAGE = <primary language> set.
- A subscriber with
MC_LANGUAGE = <each other language> in turn.
- A subscriber with no
MC_LANGUAGE set ("Not yet detected") — confirms the *|ELSE:|* fallback fires.
Phase 8 — Report
After generating, briefly summarize: which languages are covered, which path is used (segments / single conditional / TRANSLATE), where the conditional blocks live, what the fallback path delivers, and what the editor will see in the campaign builder.
Output expectations
When generating templates or campaign plans:
- For single conditional campaign: one HTML file with
*|IF:MC_LANGUAGE=...|* blocks; one campaign in Mailchimp.
- For segments + separate campaigns: one HTML file per language (parallel structure, content translated), one campaign per language segment in Mailchimp. Each file's
<html lang="..."> matches its language.
- For TRANSLATE link: one HTML file, single language, with
*|TRANSLATE:xx|* inserted at the top of the body so recipients can self-serve.
Always include the compliance footer in every language version. Always provide an *|ELSE:|* fallback for conditional blocks. Always set <html lang="..."> correctly.
Composability
This skill composes with:
mailchimp-template-language (sibling) — for the actual template HTML, MCTL placement, validation. Always load alongside this skill.damientilman/mailchimp-mcp-server (MCP) — for creating segments, uploading templates, listing audiences with their language distribution, creating per-segment campaigns.- Litmus / Email on Acid — render each language version in real clients (especially worth doing for RTL scripts and CJK).
1---2name: mailchimp-multilingual3description: Plan and build multilingual Mailchimp campaigns where one audience holds members in multiple languages, or where a brand sends across multiple markets. Use this skill when the user mentions multilingual email, multiple languages in one audience, language segments, MC_LANGUAGE, IF:MC_LANGUAGE conditional blocks, audience-level language preference, per-language content, NL/FR/DE Belgian sends, DE/FR/IT/RM Swiss sends, EN/FR Canadian sends, EN/ZH/MS/TA Singaporean sends, multi-market syndication, forking templates per market, per-market regulatory footers, or "we ship this email in three languages." Also use when the user has a single audience and asks how to localize the body of an email per recipient, or wants to choose between language segments + separate campaigns vs a single conditional campaign. Do NOT use for single-language Mailchimp templates (use mailchimp-template-language directly), for generic web/app i18n, or for professional translation workflow tooling.4license: MIT5---67# Mailchimp Multilingual Campaigns89## What this skill covers1011Campaign- and audience-level patterns for sending multilingual emails through Mailchimp. Two distinct shapes:12131. **Single list, multiple languages** — one audience whose members speak different languages. The Belgian (NL/FR/DE), Swiss (DE/FR/IT/RM), Canadian (EN/FR), and Singaporean (EN/ZH/MS/TA) case. Use Mailchimp's audience-level `MC_LANGUAGE` field plus conditional content (or segment routing).142. **Global brand, multiple markets** — separate audiences per market, sometimes separate Mailchimp accounts. Template syndication / forking workflow, per-market regulatory footers, multi-account orchestration. Bigger-org territory.1516**Template-level concerns are handled by the sibling skill `mailchimp-template-language`.** That covers the `lang` attribute, character coverage, per-script font stacks, RTL layout, and everything inside a single template file. This skill adds the audience and campaign layer on top.1718## When to use this skill1920Trigger this skill when:2122- The user is sending a campaign to subscribers who speak different languages.23- The user asks about `*|MC_LANGUAGE|*`, `*|IF:MC_LANGUAGE=...|*`, language segments, or per-language content blocks.24- The user is planning a multi-market send across separate audiences or Mailchimp accounts.25- The user asks "should I send one campaign with conditional content, or one campaign per language?"26- The user is in Belgium / Switzerland / Canada / Singapore / Luxembourg / South Africa / India / any market with multiple official languages and is sending email to all of them.2728Do **not** use this skill for:2930- A single-language Mailchimp template — load `mailchimp-template-language` directly.31- Generic web/app i18n (not Mailchimp).32- Professional translation workflow tooling (this skill orchestrates Mailchimp's built-ins; it doesn't translate text).3334## The three documented paths3536Mailchimp's own contact-languages doc (https://mailchimp.com/help/view-and-edit-contact-languages/) lists three sanctioned approaches for serving content in multiple languages. None is universally best — pick based on constraints.3738| Path | What it is | Best for |39|---|---|---|40| **Segments + separate campaigns** | Build a Mailchimp segment per language (filter on `Language` field), send a separate campaign to each segment. Each campaign has its own subject, preheader, from-name, send-time. | When the subject line / preheader / from-name / send time must differ per language — which is *most* professional sends |41| **Single campaign with conditional content** | One campaign, one subject, one send. Body uses `*\|IF:MC_LANGUAGE=xx\|*…*\|ELSE:\|*…*\|END:IF\|*` blocks to vary content per recipient. | When the subject is universal (brand name, generic phrase) and only the body needs to switch. Lower ops cost; less subject-line flexibility |42| **TRANSLATE link** | Same campaign for everyone, include `*\|TRANSLATE:xx\|*` to insert Google Translate links pointing at the campaign archive. Recipients self-serve. | The lightweight option. Fine for low-stakes informational sends; not appropriate for branded marketing where translation quality matters |4344**The bright line**: Mailchimp explicitly states *"It's not possible to translate the subject line of your email."* If the subject line must differ per language, you're on the segments path. There's no workaround.4546## Hard rules4748Things that will silently break a multilingual campaign:4950- **`*|MC_LANGUAGE|*` returns an ISO 639-1 code** like `en`, `fr`, `nl`, `de`. Mailchimp accepts a small set of locale variants too: `fr_CA`, `es_ES`, `pt_PT`. Most variants you might expect — `de_CH`, `it_CH`, `rm`, `zh_Hant` — are **not** in Mailchimp's accepted list and collapse to the base code (or are absent entirely). See `references/language-detection.md` for the full accepted list.51- **Conditional comparisons are case-sensitive.** `*|IF:MC_LANGUAGE=fr|*` matches; `*|IF:MC_LANGUAGE=FR|*` does not. Use lowercase to match the ISO codes Mailchimp stores.52- **Always provide a `*|ELSE:|*` fallback.** New subscribers default to `"Not yet detected"` until Mailchimp's auto-detection runs (or the user sets a value manually). Without an `ELSE` branch, those recipients get an empty email body. The fallback is usually the brand's primary language.53- **A conditional block must open and close within the same `mc:edit` region.** Splitting `*|IF:MC_LANGUAGE=fr|*` across two editable regions silently breaks at send time. See `mailchimp-template-language` → `references/merge-tags.md` for the block-scope rule.54- **Compliance footer must be present in every language version.** Translate the *text* (Unsubscribe / Update preferences) but keep the merge tags as-is (`*|UNSUB|*`, `*|HTML:LIST_ADDRESS_HTML|*`). Address and unsubscribe link are not optional in any locale.55- **Language preference is a system-level field, not a custom merge field.** Don't try to set it via `*|MERGE5|*` or similar; use Mailchimp's built-in Language attribute (auto-detected from browser, exposed on signup forms, manageable via API and CSV import).5657## Workflow5859When asked to plan or build a multilingual campaign, work through these phases. Each phase points to the reference file that owns the detail.6061### Phase 1 — Identify the shape6263Single-list-multilingual (one audience, many languages) or multi-market-global-brand (multiple audiences, often multiple accounts)? Confirm with the user. The patterns and reference files differ.6465For multi-market work, **load `references/multi-market.md`**.6667For single-list-multilingual (the default and best-supported shape in Mailchimp), continue.6869### Phase 2 — Map the constraints7071Ask the user — or infer from the brief:72731. **Which languages?** Get the list and the priority (which is the "primary" / fallback).742. **Must the subject line differ per language?** If yes → segments path is forced. If no → conditional-content path is viable.753. **How is language preference captured today?** Browser auto-detection (Mailchimp's default), signup-form field, CSV import, or unset on all contacts? If unset, the user needs to set it before sending matters.764. **Are there per-language regulatory differences?** Different compliance footer text, currency, jurisdiction. Single-list-multilingual generally implies one jurisdiction (Belgium has one address); multi-market implies many.7778### Phase 3 — Choose the path7980**Load `references/segments-vs-conditional.md`** to walk the decision tree and apply the choice to the user's constraints.8182### Phase 4 — Establish how language is captured8384**Load `references/language-detection.md`** to confirm how `MC_LANGUAGE` gets populated and what values are allowed. If the user's audience has mostly `"Not yet detected"` contacts, this is the gate — language-aware sends only work once language is set on contacts.8586### Phase 5 — Build the template8788**Load `mailchimp-template-language` (the sibling skill)** for the actual HTML scaffold, `mc:edit` placement, responsive structure, accessibility, and validation. This skill doesn't duplicate that work — it composes with it.8990When the path requires conditional content blocks (single-campaign approach, or hybrid where some sections vary per language but the subject doesn't), **load `references/conditional-content.md`** for the `*|IF:MC_LANGUAGE=...|*` patterns: per-language hero, CTA, compliance footer, signature block.9192### Phase 6 — Validate9394Two layers:95961. **Structural**: run `mailchimp-template-language/scripts/validate.py` on each template file. Same validator as the monolingual flow.972. **Multilingual completeness** — manual checklist:98 - Every conditional block has an `*|ELSE:|*` fallback for `"Not yet detected"` contacts.99 - Every language's content path includes the compliance footer.100 - The `lang` attribute on `<html>` matches the dominant language of the template (for the segments path, set per-segment).101 - Font stacks cover every script the languages need (see `mailchimp-template-language/references/typography.md`).102103### Phase 7 — Test104105Mailchimp's "Preview & Test → Enter preview mode" lets you fill merge tags with the data of a chosen subscriber. Preview against at least:106107- A subscriber with `MC_LANGUAGE = <primary language>` set.108- A subscriber with `MC_LANGUAGE = <each other language>` in turn.109- A subscriber with no `MC_LANGUAGE` set (`"Not yet detected"`) — confirms the `*|ELSE:|*` fallback fires.110111### Phase 8 — Report112113After generating, briefly summarize: which languages are covered, which path is used (segments / single conditional / TRANSLATE), where the conditional blocks live, what the fallback path delivers, and what the editor will see in the campaign builder.114115## Output expectations116117When generating templates or campaign plans:118119- For **single conditional campaign**: one HTML file with `*|IF:MC_LANGUAGE=...|*` blocks; one campaign in Mailchimp.120- For **segments + separate campaigns**: one HTML file per language (parallel structure, content translated), one campaign per language segment in Mailchimp. Each file's `<html lang="...">` matches its language.121- For **TRANSLATE link**: one HTML file, single language, with `*|TRANSLATE:xx|*` inserted at the top of the body so recipients can self-serve.122123Always include the compliance footer in every language version. Always provide an `*|ELSE:|*` fallback for conditional blocks. Always set `<html lang="...">` correctly.124125## Composability126127This skill composes with:128129- **`mailchimp-template-language`** (sibling) — for the actual template HTML, MCTL placement, validation. Always load alongside this skill.130- **`damientilman/mailchimp-mcp-server`** (MCP) — for creating segments, uploading templates, listing audiences with their language distribution, creating per-segment campaigns.131- **Litmus / Email on Acid** — render each language version in real clients (especially worth doing for RTL scripts and CJK).
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