The 1940s in Britain was a high point for hand knitting.
Women on the home front could make a contribution to the war effort by knitting for the troops using patterns that were often given away free. Many specialised patterns developed such as the balaclava helmet with ear flaps for use in telephone operations or the mittens with a separate forefinger for firing a trigger in the cold.
Once the war was over both clothing and knitting wool were still rationed but people turned to knitting as a cheap way to enhance their wardrobes. Fine wool and pretty lacy patterns became fashionable.