- 1900s–1920s warrant-chief impositions across the central Ijaw clans — the British appoint chiefs without traditional legitimacy in the acephalous Ijaw clan system, a structural grievance that surfaces in every later Delta uprising.
- 1929 Women's War — the eastern flank reaches into Ogbia and the Brass division; tax-and-census protests follow the Aba pattern.
Bayelsa State · Crisis deep dive
Early colonial (1900–1929)
Methodology
Tier 1 · primary
Courts. Gazettes. National archives.
Tier 2 · corroborating
OCCRP. HRW. BudgIT. TheCable.
Tier 4 · tertiary, flagged
Wikipedia only where primary is pending. Always labelled.