The collection of tax records here were created by numerous agencies and officials in a complex taxation system; due to this, they were described as one record group for the convenience of researchers. The exceptions to this grouping are the related records of the Appeal Tax Court (BRG5) and the Baltimore City Collector (BRG40).

The following description and series details are drawn from a typescript guide to the record groups at the Baltimore City Archives."RG" is equivalent to "BRG."

The taxation system prior to the city charter of 1796 was completely dependent upon the state government. The origin of a general property tax dates back to 1750, when the Baltimore Town Commissioners were allowed to levy a tax of one shilling, six pence on every one hundred pounds of assessed property. This aspect of taxation remained in force until the charter incorporated that document. The creation of the Baltimore Town Special Commissioners (1782) and the Board of Port Wardens (1783) also introduced other special taxes and fees.

The new municipal government in 1797 brought autonomy to many aspects of the town's political life. Although taxation was still dominated by the state, the charter of 1796 began an evolution towards a modern, autonomous taxation system for the city. The earliest development was the creation of a City Collector (RG. 40) and City Register (RG. 32). The collector was generally responsible for enforcing payment of municipal taxes and dues, and the register primarily functioned as treasurer. Prior to 1856 the tax records were probably maintained by either the collector or register with duplications possibly existing in both offices. (The tax books from 1856 on are clearly identified as part of the City Collector's records.)

The responsibilities of these offices were continually modified through the nineteenth century. The Appeal Tax Court (RG. 5) was created in 1841 (consisting of two assessors and the City Collector) to serve as a Board of Review and Assessments. In 1852/53 the City Auditor (RG. 6) was created to oversee municipal taxes, assessment collections, and collections of arrearages. This office was gradually absorbed by the City Comptroller (RG. 43) established in 1857, who supervised the entire financial affairs of the municipality. Throughout the entire nineteenth century, the state authorized reassessments of city property. These reassessments required the hiring of special commissioners and the division of the city into special districts. Such reassessments occurred in 1785, 1792, 1812, 1817, 1822, 1832, 1852, 1866, 1876 and 1896.

With a new charter in 1898 the municipal government became autonomous in property taxation. The charter created a Department of Finance which included the Comptroller, City Register, City Collector, Collector of Water Rents and Licenses, Commissioners of Finance, and Board of Estimates (RG. 36). After 1900 it was mandatory to revise assessments unrelated to state, at least once every five years. The Appeal Tax Court which was steadily becoming a more important organization, was strengthened with a provision in 1904 that gave the court two real estate experts as assessors.

Researchers desiring more information should consult Jacob H. Hollander, The Financial History of Baltimore (Baltimore: Johns Hopkins Press, 1899); Leonard Owens Rea, The Financial History of Baltimore 1900-1926, Johns Hopkins University Studies in Historical and Political Science, Series 48, No. 3 (Baltimore: Johns Hopkins Press, 1929); Gary Lawson Browne, Baltimore in the Nation, 1789-1861 (Chapel Hill: University of North Carolina Press, (1980); and Dennis Rankin Clark, "Baltimore, 1729-1829: The Genesis of a Community" (Ph.D, Catholic University of America, 1976).