Add an event

A single historical event — a battle, a treaty, a coronation, a published work. The form generates a JSON file you can submit three ways.

What makes a good event entry

Specific. "Battle of Panipat (1526)" not "Mughal conquest of north India".
Verifiable. A date, a place, named participants. If you can't pin all three, it's probably not an event — it's a process.
Sourced twice. Cross-check against at least two independent sources before marking verified.
Well-pinned. The pin should be at a real place: the actual battlefield, the building where the treaty was signed, the city where the conference was held.

1. Identity

Title, ID, and the short captions that appear when someone hovers over the pin or opens the popover.

Title * ≤ 60 chars

Display name. Sentence case. No date — that goes in the tooltip.

0 / 60

ID *

Globally unique, kebab-case (lowercase, digits, hyphens). Auto-suggested from your title — feel free to edit. Once published, never changed.

Tooltip * ≤ 80 chars hard cap

One-line caption shown on pin hover. Should include a date or place anchor — read like a museum label. e.g. "Jallianwala Bagh massacre, Amritsar, 1919"

Summary * ≤ 160 chars hard, ≤ 140 soft

One sentence. Shown in the popover and in cross-reference cards. The reader's first taste — must stand alone.

0 / 160

Detail * 80–150 words

Editorial paragraph for the right panel. Direct, calibrated, named entities and numbers over adjectives.

0 words

2. When

Use YYYY, YYYY-MM, or YYYY-MM-DD. For BCE dates, prefix with a hyphen — e.g. -322 for 322 BCE. For multi-day events, set start and end to different dates.

Start date *

End date *

Precision *

Approximate?

Display string *

How the date should read in the UI. e.g. "21 April 1526" or "April 1917 – May 1918"

3. Where

Click the map to drop a pin. Drag it to refine. Or paste lat/lon manually below. For a route (a journey across multiple points), choose "route" type and add additional points.

Location name *

Specific place. e.g. "Jallianwala Bagh, Amritsar"

Region optional

Larger area for context. e.g. "Punjab", "Bombay Presidency"

Location type *

Country *

ISO code. Use OFF for events outside the asset's bounding box (London, NYC, etc.).

Pick the location on the map

Click on the map to drop a pin.

Latitude *

Longitude *

4. Era and categories

Era is a coarse time bucket (used for the timeline bands). Categories tag the kind of event (used for the colored pills).

Era *

Categories * tick at least one

Figures comma-separated names

Major named participants. e.g. "Babur, Ibrahim Lodi, Ustad Ali Quli"

Tags comma-separated, kebab-case

Free-form thematic markers. Drives filtering and collection membership. e.g. "rebellion, women-leaders, institution-founding". Different from Categories above (which is a controlled vocab driving pin colour).

5. Links and sources

A Wikipedia link is required. Sources are optional but strongly encouraged — they're how reviewers verify your claims.

Links *

Sources scholarly preferred

6. Causal links optional

If your event was directly caused by an earlier event already in the corpus, link it here. Each link needs a gloss — the editorial sentence explaining the connection.

Caused by

Use the event's id (e.g. first-battle-of-panipat-1526). You can find ids in the existing data files at data/events/.

7. Verification

Have you cross-checked against ≥2 independent sources? *

Validation

Fill in the form above; errors will appear here as you type.

Preview

This is the JSON your contribution will become. Review before submitting.

// fill in the form to see the preview

Submit your contribution

Download saves the JSON to your computer (no GitHub account needed). Pull request opens GitHub's web editor with the file pre-populated; you click "Propose new file" and a PR opens. Issue opens a GitHub issue with the JSON in the body — use it if your contribution needs editorial discussion first.