Territory Changes

305 events since 1945 · 51.9M km² transferred

Territory Gained/Lost Countries Created/Dissolved Pre-1816 Events

All Time Since 1500 Since 1776 Since 1900 Since 1945 Since 1990

Data quality:1900+ comprehensive (COW dataset)1816–1899 sparse (many events from unrecorded polities)Pre-1816 historical estimates only

New Countries

132

94 independence
24 secession
14 partition

Dissolved

since 1945

Expanded

139

28 via conflict
111 peaceful only

Contracted

15 via conflict
9 peaceful only

Based on 305 recorded events (64 by conflict · 51.9M km² transferred)

Notable Historical Events (pre-1816)

Estimated figures from historical sources. Not included in the ranked totals on the main tab.

No pre-1816 events in the selected period. Choose an earlier time range (e.g. All Time or Since 1500) to see historical events.

Ranked totals based on event-level records (1816-2025). Pre-1816 events are historical estimates shown separately. Area in square kilometers. Events classified as conquest, annexation, cession, secession, unification, or mandated territory. Wartime occupations (e.g., WWII) are excluded from the dissolved list.