17 September on the map of history
6 events the records the map draws date to 17 September, from 1888 to 1969. Each one opens the map on that very day.

- 1888
- 1914
The Race to the Sea — each army tries to outflank the other northwards until the coast stops both
War record · World War I · 1914-09-17 – 1914-10-19
Open the map on this day → - 1939
The Red Army crosses into eastern Poland on the sixteenth day
War record · World War II
Open the map on this day → - 1939
The first battle of Changsha — the Japanese reach the city and pull back to their start line in three weeks
War record · World War II · 1939-09-17 – 1939-10-06
Open the map on this day → - 1944
Operation Market Garden
War record · World War II · 1944-09-17 – 1944-09-25
Open the map on this day → - 1969
The map stops drawing West Irian (Indonesia); new borders for Indonesia
Border record (CShapes 2.0)
Open the map on this day →
What this page states
A border event is what the border record states about its own outlines, under the names IntMap’s map writes on that day: «the map begins drawing», «stops drawing», «new borders for». It is computed by the map’s own code, comparing the day with the day before.
A name the record does not date is not listed: the map’s table of era names is written in years, so a renaming that falls on another country’s border day is left out.
OpenHistoricalMap, which the map draws from 1689 to 1885, is not included: its dates carry no precision, and most of its first-of-the-month dates are months or years written as days.
The war record covers only the wars IntMap documents day by day (World War I, World War II, Korean War, Vietnam War, Arab–Israeli Wars, Yugoslav Wars).
Sources
CShapes 2.0 (Schvitz et al. 2022, icr.ethz.ch/data/cshapes) · CC BY-NC-SA 4.0
Territory and dates: the documented record, compiled in scripts/wars/. Country outlines: CShapes 2.0 (Schvitz et al. 2022, icr.ethz.ch/data/cshapes).