rdeknijf/collectie-overijssel

Collectie Overijssel (HCO)

Collectie Overijssel (formerly Historisch Centrum Overijssel, HCO) is the provincial archive for Overijssel. Based in Zwolle, it holds records for all municipalities in the province.

Website: https://collectieoverijssel.nl

Coverage

Indexed and searchable (via API)

• BS Geboorte (civil births) — 1811+
• BS Huwelijk (civil marriages) — 1811–1932
• BS Overlijden (civil deaths) — 1811–1960
• Total: ~2M records, 7.2M person references
• Coverage: ALL Overijssel municipalities

NOT indexed (scans only, HUMAN action)

• DTB Dopen (baptisms) — pre-1811 church records
• DTB Trouwen (marriages) — pre-1811 church records
• DTB Begraven (burials) — pre-1811 church records
• Bevolkingsregister (population registers) — not in current dataset

DTB records have been digitized as scans on collectieoverijssel.nl but are NOT searchable by person name. Indexing is in progress ("in the coming years"). For pre-1811 research in Overijssel, use FamilySearch films or browse scans directly on the HCO website.

Access method: OpenArchieven JSON API

Uses the standard OpenArchieven API with archive=hco. No login or API key required. Sub-second response times.

Search by person name

curl -s "https://api.openarchieven.nl/1.0/records/search.json?archive=hco&name={surname}&number_of_records=10"

Search with filters

curl -s "https://api.openarchieven.nl/1.0/records/search.json?archive=hco&name={surname}&eventplace={place}&number_of_records=10"

Search parameters

| Parameter | Description | Example | |-----------|-------------|---------| | archive | Always hco | hco | | name | Surname (required for search) | Knopers | | eventplace | Filter by place | Holten | | sourcetype | Record type filter | BS Huwelijk | | period_start | Start year | 1850 | | period_end | End year | 1900 | | number_of_records | Results per page (max 100) | 25 | | start | Pagination offset | 0 |

Source type values: BS Geboorte, BS Huwelijk, BS Overlijden

Note: The place parameter does NOT work for HCO — use eventplace instead.

View full record detail

curl -s "https://api.openarchieven.nl/1.0/records/show.json?archive=hco&identifier={UUID}"

Returns A2A XML-style JSON with all persons in the record, their roles, dates, places, and archive references.

Browse record on OpenArchieven (with scan links)

https://www.openarchieven.nl/hco:{UUID}

Output format

When reporting findings from HCO:

**Source:** Collectie Overijssel, {sourcetype}, {place}, {date}
**Archive ref:** HCO via OpenArchieven, ID {UUID}
**URL:** https://www.openarchieven.nl/hco:{UUID}
**Confidence:** Tier B — official civil registry record from Collectie Overijssel

Municipalities covered

All of Overijssel province, including but not limited to:

• Salland: Deventer, Diepenveen, Olst, Raalte, Heino, Dalfsen, Ommen
• Twente: Enschede, Hengelo, Almelo, Borne, Delden, Goor, Markelo, Holten, Rijssen, Wierden, Haaksbergen, Losser, Oldenzaal, Denekamp
• Kop van Overijssel: Kampen, Zwolle, IJsselmuiden, Zwartsluis, Hasselt, Genemuiden, Staphorst, Meppel-adjacent
• Vechtdal: Hardenberg, Gramsbergen, Coevorden-adjacent
• Land van Vollenhove: Vollenhove, Blokzijl, Steenwijk-adjacent

Limitations

1. No DTB records — pre-1811 church records are NOT in the API. For pre-1811 research, browse scans on collectieoverijssel.nl or use FamilySearch films.
2. No bevolkingsregister — population registers are not indexed.
3. Place filter requires eventplace — the place parameter returns an API error for HCO. Always use eventplace for place filtering.
4. Birth records partially indexed — births 1811–1912 are being added incrementally. Some may be missing.

For pre-1811 Overijssel research

When DTB records are needed and this skill can't help:

1. FamilySearch catalog — search for the municipality + "Doop" or "Trouw" or "Begraaf". Many Overijssel DTB films are digitized.
2. collectieoverijssel.nl → Onderzoek → select municipality → browse DTB scan images directly (HUMAN action, not API-searchable).
3. AlleFriezen (tresoar.nl) — for Overijssel municipalities near the Friesland border.
4. WieWasWie — sometimes has Overijssel DTB records indexed from other contributing archives.

Parallelizable

No browser needed — run multiple API queries simultaneously.