War was declared on 3rd September 1939 and the two Territorial Army battalions, the 4th and the 6th, were called-up immediately. The 2nd battalion embarked for France in October 1939 and were followed by the 6th battalion in April 1940.  Both managed to return to England via Dunkirk more or less intact.  The 1st battalion, in India, didn't really come into action until 1942.

It was the Territorials of the 4th battalion who were the first to see action--indeed it is quite probable that they were the very first British soldiers to come into contact against an advancing enemy in the field in WW2.  They had been sent to Norway, but ill-equipped and without air support they had to be evacuated.  Within a few weeks they were sent to garrison neutral Iceland. They trained as alpine troops during the two years they were there. 

The 6th battalion left for Algiers in January 1943 and had their baptism of fire at a village called Sedjenane which was lost and then regained after fierce fighting. In September 1943 they took part in the assault landing at Salerno in Italy.  After a hard campaign in Italy they returned to Egypt to refit in March 1944, by which time they had lost 518 killed, wounded or missing.  They returned to Italy in July 1944 and after more hard fighting they sailed for Greece in December to help the civil authorities to keep order now that the Germans had left.  In April 1945 the 6th Lincolns returned to Italy and then moved into Austria for occupation duties.

The 2nd battalion landed in Normandy on D-Day and the 4th battalion followed them four days later.  Both were subsequently in heavy action around Caen.  The 4th battalion helped in the capture of Le Havre whilst the 2nd Lincolns were in Holland by the end of September 1944.  The 4th battalion, further west, crossed the Antwerp-Turnhout canal in the dark and in the pouring rain to secure a bridgehead for the Engineers, who quickly erected a bridge for the Polish Armoured Division.  The Allied advance ground to a halt during the winter in flooded Holland, but in February 1945 the 2nd Lincolns crossed the Maas and by the 24th they were in Germany.  They were involved in a number of close actions and by VE Day they had reached Bremen.  The last action of the 4th Lincolns was in the liberation of Arnhem in April 1945.