The series of United States one-dollar bills that began in 1969 were unique in that they featured an updated seal for the United States Treasury. The new seal featured a more simplified design, and the focal image of the shield was given a more square shape.
The most profound difference in the revised seal on the 1969 dollar bill was the inscription that could be found around the circumference of the seal. Prior to the 1969 series, the inscription read "Thesaur. Amer. Septent. Sigil" which is an abbreviation for "Thesauri Americae Septentrionalis Sigillum," or "The Seal of the Treasury of North America". On the 1969 dollar bill, these words were simplified further to read "The Department of the Treasury, 1789".
1969 also signified the end of the higher note denominations in United States money supply. The United States Treasury had discontinued printing the $500, $1000, $5000 and $10,000 notes back in 1934, leaving the $100 bill as the largest. By 1969, the supply was running out, but the demand for bills over $100 had declined to the point that the Treasury decided it was more cost-efficient to remove the notes from circulation instead of printing another series, and it destroyed the ones it still retained in its vaults.