The strike was Britain's first national postal strike and began after postal workers demanded a pay rise of 15-20% then walked out after Post Office managers made a lower offer. The strike began on 20 January and lasted for seven weeks, finally ending with an agreement on Thursday 4 March. After voting over the weekend, the strikers returned to work on Monday 8 March 1971. The strike overlapped with the introduction of decimal currency in the U.K.