Prior to Theodore's birth, his parents had decided to emigrate to the United States in 1879 to avoid the introduction of Russification in their native country, Russia.

It was in this position that he published his first paper in 1939, European Archival Practices in Arranging Records, which laid the groundwork for his life's work.

His work there illustrated the many difficulties found in managing vast amounts of government records, which only increased his commitment to finding solutions.

[2] One of his first projects was to craft a rigorous training program for NARA employees because there was an inadequate standardization in his division's policies and procedures.

[8] He spent months helping address records management concerns through a lecture and seminar series that allowed him to travel throughout the continent and even to Tasmania and New Zealand.

During this time, his lecture and seminar notes began to take the shape of a textbook on archival work and management practices.

[4] The book explores emerging issues, concerns, and approaches to archival theory and practice that modern archivists encounter, thereby reflecting the desire for a closer and more efficient working relationship between records management and archival work and giving readers a broad overview of principles of public records management.

"[9] In the following year, Schellenberg won a meritorious service award to honor the contributions made to the archival profession through the textbook.