Evergreen date guide

What is celebrated on September 21?

For 2026, these source-backed observances resolve to Monday, September 21. Recurring rules can move in another year, so each record keeps its own date logic.

Date authority profile

What this date contains

10 unique authority records

The list is deduplicated at the public entity layer while retaining all research provenance behind each page.

0 stable or rule-calculated

0 fixed annual and 0 reusable rule-based records can be placed without inventing a new date.

0 edition-specific

Edition-specific dates appear only when the requested year matches the verified edition; variable and historical records remain gated.

6 explicit country-scope records

Country scope stays attached to the underlying record instead of being generalized into a worldwide observance.

1 reviewed in-depth guides

These entities add reviewed meaning, history, activities, facts and FAQs without rewriting the authority facts.

Curated global anchors

Major global guides on September 21

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A reviewed starting point drawn from prominent global observances with strong institutional or organizer provenance. Selection does not change each record’s official status or scope.

Source-backedFixed AnnualIn-depth guide

International Day of Peace

21 September · United Nations / international observance

A/RES/36/67

Explore the mix

Topics represented on September 21

All topics →

Civic, Remembrance & History 3 Health, Wellness & Awareness 3 Community, Causes & Advocacy 2 Food, Drink & Hospitality 1 Arts, Entertainment & Lifestyle 1

10 date-resolved records

All observances on this date

Source-backedFixed Annual

Belize Independence Day

21 September · Belize

The Organization of American States’ current country page lists Belize National Independence Day as 21 September.

Source-backedFixed Annual

Independence Day

21 September · Armenia

The Government of Armenia’s Independence Day message is dated 21 September and explicitly identifies the occasion as Republic of Armenia Independence Day.

Source-backedFixed Annual

Independence Day

21 September · Malta

Australia’s Department of Foreign Affairs and Trade current National Days protocol register lists Malta — Independence Day on 21 September. The source verifies the diplomatic national-day i…

Source-backedFixed AnnualIn-depth guide

International Day of Peace

21 September · United Nations / international observance

A/RES/36/67

Source-backedFixed Annual

National Cat & Dog Gut Health Awareness Day

21 September · Pet-health awareness / AnimalBiome-sponsored campaign; veterinary-calendar corroboration

AnimalBiome’s press material documents the awareness-day launch, while Animal Medical Center veterinary-awareness calendars repeatedly list National Cat & Dog Gut Health Awareness Day on Se…

Source-backedFixed Annual

National Opioid Awareness Day

21 September · United States / opioid-awareness observance recognized by the Indian Health Service

The U.S. Indian Health Service identifies September 21 as National Opioid Awareness Day in its public-health education material.

Source-backedFixed Annual

National Pecan Cookie Day

21 September · United States / informal food-observance usage; date corroborated by a public university event and a dedicated calendar source, with origin unresolved

The University of North Texas scheduled a National Pecan Cookie Day event on September 21, 2023; National Day Calendar likewise places the recurring informal observance on September 21 whil…

Source-backedRule Based Annual

Respect for the Aged Day (敬老の日)

Third Monday of September; 21 September 2026 · Japan / national holiday rule

Japan’s Cabinet Office explains that Respect for the Aged Day has fallen on the third Monday of September since 2003; in 2026 that is 21 September. It separately identifies 15 September as…

Source-backedFixed Annual

World Alzheimer’s Day

21 September · Organizer-backed international observance

Alzheimer's Disease International (ADI)

Source-backedFixed Annual

World Mini Golf Day

21 September · International / informal miniature-golf observance

National Today places World Mini Golf Day on September 21, while Days Of The Year independently lists Miniature Golf Day on the same annual date.

How this date is built

This page is assembled from verified fixed dates, reusable recurrence rules, and target-year records whose edition matches 2026. Variable, historical or unresolved records are not silently forced onto this date.

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