When Hitler came to power in 1933, British leaders worried that a new war might begin. By 1934, afraid that British cities and towns would be targets for bombing raids by aircraft, officials made secret plans to move infants, schoolchildren and some adults to the countryside if war began.

In 1938, during the Munich crisis, evacuation was very nearly started in Britain, but war was avoided and children remained at home. More detailed evacuation plans were prepared after the crisis. Evacuation was to be voluntary, with parents deciding whether to send their children away.

A year later, in September 1939, evacuation commenced several days before Britain entered the war. From the cities and big towns, schoolchildren, their teachers, mothers with children under five, pregnant women, and some disabled people were moved by train and road to smaller towns and villages in the countryside. The evacuation plan worked very well and 1½ million children and adults were moved within 3 days, including 600,000 from London. The government was disappointed because it had hoped to evacuate 3 million people. More than half of all schoolchildren did not leave their homes in the cities and towns.

There were no big bombing raids on Britain in the first months of the war and, by early 1940, many children had returned home.

In June 1940, following the defeat of France, people were afraid that towns on the east and southeast coasts of England would be bombed, and there was a large evacuation of children from these towns to safer areas.

When heavy bombing raids started in the autumn of 1940 - the Blitz - another big evacuation began.