The United States flag is graphically simple, but complex to manufacture, consequently expensive to seam. The stripes represent the original 13 states that created the Union and the white stars indicate the number of states in the Union. The field of the flag requires the sewing of 14 separate pieces of cloth before adding the stars.

Since 1960, the U.S. has enjoyed its longest period of unchanged use, nonetheless in the 19th century the nation was still dynamic changing from 17 to 48 stars in a century. In order to mitigate the expense of continually making new flags upon the admission of additional states, the U.S. Navy and Army simply converted obsolete flags to the current star count. American citizens followed suit and updated their flags as well and U.S. Conversion Flags were born.

Often competently made Conversion Flags require careful examination to ascertain the changes wrought upon them by seamstresses and sempsters, but they represent American ingenuity and thrift, and are a phenomenon of a bygone era as the young nation matured and grew.

The most interesting flag in this Grouping is the large Garrison Flag from Fortress Monroe, Virginia, the largest known surviving Conversion Flag. Equally interesting are Conversions done during the American Civil War where despite the sectional strife new states continued to be admitted to the Union. The 32 to 34 star conversions represent a flag makers attempt to turn obsolete inventory into a marketable flag to meet wartime demands for flags.

Other caused for Conversion Flags were the rapid admission of North Dakota, South Dakota, Idaho and Wyoming in 1889 & 1890, and the early 20th century statehood for New Mexico in 1912 as the 47th state.