The initials DTJ stand for "Delnicke Telocvicne Jednoty" or "Workers' Gymnastic Union". DTJ as an organization is a part of the great Labor Movement as the translation implies. It is an International organization, whose program consists of training the youth of the world to enable it to take part in the great movement for a better and more just organization of human society.
A Little History
The DTJ organization was formed by a group of tailors in Prague, 1897. The group was sympathetic towards the Social Democratic movement of that period. Gym work was started immediately, classes being held wherever room could be found, mostly at the Inns.
The first DTJ group to be formed in America was founded in Cleveland, Ohio by members of the Lassalle Senior Club in 1909. Soon after another group was organized in Chicago, Illinois. An organization affiliated with the DTJ is the American Sokol of New York. Although the D.A.S. has a sick and death benefit provision in its program, there is possibility that it will come in closer contact with the DTJ of the future.
-DTJ Taborville website. (Beware Czech music!)