In January 1939, Chadwick journeyed to Czechoslovakia to accompany two refugee children back to Britain where they had been admitted to his school. He met another refugee child, Gerda Mayer, in
Prague, interviewed her and her family, and took her along with the other two children. Chadwick's mother sponsored Mayer, putting up the guarantee of 50 pounds which the British government required to admit refugee children to Britain. Chadwick described his initial reaction to the situation in Prague: "We got a clear impression of the enormity of the task. We so often saw halls of confused refugees and batches of lost children, mostly Jewish, and we saw only the fringe of it all." After delivering the first three children to Britain, Chadwick returned to Czechoslovakia to help rescue more children by sending them to Britain. Thousands were on a list for possible rescue, but he could only save hundreds. In Britain,
Nicholas Winton worked to get visas for children to be granted entry. Working with the
British Committee for Refugees from Czechoslovakia headed by
Doreen Warriner, Chadwick had the task of selecting children for the
kindertransport and organizing their departure. His first operation, 14 March 1939, was a 20-seat airplane evacuation from Prague which he accompanied. Later, the evacuation of children was by train. Chadwick accompanied the children to the Prague Railroad Station, from where the children, with adult escorts, notably Quaker
Tessa Rowntree and Unitarian
Martha Sharp, journeyed by rail through
Poland or Nazi Germany to seaports on the
Baltic Sea or in the Netherlands from where they sailed to Britain. On 15 March 1939, the situation in Czechoslovakia became more dangerous. German troops occupied the whole Czech part of the country. The German crackdown stimulated a large market in forged passports and exit documents in which Chadwick was probably involved. Warriner and many other refugee workers found it prudent to leave the country to avoid arrest. On 2 June 1939, Chadwick saw off a trainload of 123 children and left Czechoslovakia shortly thereafter, possibly fearing arrest by the German
Gestapo for forging documents. With his departure,
Beatrice Wellington became the sole representative of the British Committee in Czechoslovakia. The evacuation of children continued. All together, until it was shut down with the declaration of war on 1 September 1939, the
kindertransports escorted 669 children out of Czechoslovakia. Winton, who was honoured many years later for his participation in the
kindertransport, acknowledged the vital roles in Prague of Chadwick, along with Doreen Warriner, diplomat Robert J. Stopford, Beatrice Wellington, Josephine Pike, and Bill Barazetti. Of Chadwick, Winton later wrote, "Chadwick did the more difficult and dangerous work after the Nazis invaded… he deserves all praise". ==Later life==