Three groups, Protestation, Collection and Taxation records, provide the most important sources in the Guide. The far fewer records of the previous decade and the following years of Civil War and Commonwealth have also been included. With this finding-aid, it should be possible to draw valid conclusions about people and places in the 1640s, a demographically obscure period before the Hearth Tax Returns of 1662 and subsequent years.The Protestation, a form of oath of loyalty, ostensibly to the King, but in fact to Parliament, was initiated in the House of Commons in May 1641, when Members themselves took it. Nine months later the scope was very vastly widened, when instructions went out that it should be taken by every adult (male); very ocasionally women were also recorded.Closely associated with the Protestation was the Collection in Aid of Distrssed Protestants in Ireland; The oath was taken and the collection made, often simultaneously, in February 1641/42 and March.Parliament-approved taxation records recommence, after Charles I's eleven years of personal rule, with Tudor-type Subsidies, to be collected during 1641. In July 1641 a Poll Tax was voted, but few records of this survive. Thirdly, an Assessment or Grant was agreed, to be collected in May and November 1642. This Assessment had a much lower tax threshold, and consquently many more taxpayers are named.