From 1943 to 1944, the United States Army used the cathedral as an anti-aircraft training facility; the evidence of this era can still be seen in murals in the crypt.

In 1944, Bishop S. Arthur Huston reopened discussions with the parish's bankers in St. Louis, Missouri; over the next three years, more funds were raised, and in 1947 the mortgage was paid.

[1] The cathedral's dean, Robert V. Taylor, resigned abruptly in March 2008, stating that he and the vestry (church board) diverged in their visions for the future of St. Mark's and there was a loss of trust between them.

[2] After several years of transitional ministry, Taylor was succeeded by Steven Lynn Thomason in the summer of 2012.

[4] St. Mark's Cathedral is located at the top of a very steep drop-off to Lakeview Boulevard East below.