Examples of valid series IDs are C55, SE196, TM18.
Understanding Maryland Records
Oaths and Censuses of the Revolutionary Period
In 1776 the Council of Safety, the governing body of Maryland at that time, conducted a census for the purpose of setting Maryland's quota for a tax to support the Revolutionary War. Some schedules list heads of households only, grouping the other members of the household by age, sex, and race. Others name each individual, recording their age, sex, and race.
The General Assembly (Oct. Term 1777, Ch. 20) passed an act requiring every male within Maryland above eighteen years of age to take an Oath of Fidelity to the state. Exemptions were specified for Quakers, Mennonites, Dunkers, and individuals already serving in the military. The oath stated: "I do swear I do not hold myself bound to yield any Allegiance to the King of Great Britain, his heirs or successors and that I will be true and faithful to the Sate of Maryland and will to the utmost of my power, support, maintain and defend the Freedom and Independence thereof and the Government as now established against all open enemies and secret and traitorous conspiracies ..."
There was considerable incentive to take the Oath. If a man did not, he had to pay triple the amount of his assessment for taxes each year during his lifetime. He was not allowed to file any suit in any court, nor could he be a tradesman, practice law, medicine, or surgery, preach the gospel, teach in any school, or hold any office, civil or military. In order to identify those who did not take the Oath, a census was taken in 1778 of all males 18 years of age and older on or before March 1, 1778.
Maryland Indexes (Oaths of Fidelity, Index), 1778 MSA S1420