A verb meaning ‘to move a large area of land through time to another era’. For example, ‘2006 Germany ISOTed to 1942’ would mean the territory of 2006 Germany replacing that of 1942 Germany, leaving the rest of the 1942-Earth to react to this strange event.

However, the term is often just used in lieu of ‘time travel’ these days rather than just being applied to large areas, e.g. ‘Hitler ISOTed to the Bronze Age’.

Commonly associated with ASBs.

It is generally assumed that if you ISOT modern France to 1932 then 1932 France would in turn come to the modern world in an exchange. However, some people have instead suggested that 1932 France (or whatever) instead goes to an empty waterworld known as The Output.

ISOT is derived from S.M. Stirling’s Island in the Sea of Time trilogy. ISOT is sometimes said to stand for ‘Island Sea Of Time’ and sometimes ‘In Sea Of Time’, which makes more sense.

Many published AH works are based on ISOTs, including the aforementioned Island in the Sea of Time books, Eric Flint’s 163X series, and Harry Turtledove’s The Misplaced Legion.

In addition to this, several AH.com stories are based on ISOTs: Chris’ Second Chance trilogy, Thande‘s Moonstruck trilogy, and many more.

The actual name ‘ISOT’ is rarely used in published fiction. In 163X it is termed the ‘Ring of Fire’, in ISOT itself it is termed ‘the Event’, and so forth.