Eugene was the only son of Dr. John William Crowdus and Fanny Bell Hammond. He came to Texas with his family at a young age. He had five sisters. Later, he with his father and others founded the Crowdus Wholesale Drug Company and he served as the Chief Operating Officer for much of his working life. On 6 June 1883, he married Miss Elmina Albertina Wolfe who had been born in New Orleans and her family had just moved to Dallas. He was married in her parents home. Elmina gave birth to a son, John William Crowdus in 1884. Elmina became ill with Dengue Fever and was administered an accidental overdose of morphine which was being used to treat the disease and died 7 October 1885 in Dallas, and she is buried in Greenwood Cemetery with her Wolfe family. On 15 June 1893, Eugene took a second wife in Waco, Texas at her parent's home when he married Miss Judith Olive. He promised her a new brick home in Dallas if she would consent to marriage. She held out until the home was built at 1000 South Ervay and after a long Honey Moon in Europe she returned to Dallas to live all of her live in this home. One son, Sidney Crowdus named after her father was born of this union, but he died in 1906 at the age of 10 or 11. In 1917, Eugene died and in accordance with his will was buried in Oakland Cemetery. In his will he asked that a trust fund be created and a suitable mausoleum be built there, with perpetual care and flowers placed on it once a week. This mausoleum was never built, and Eugene was buried in the Crowdus plot in Oakland with some of his relatives. He apparently only left about $30,000 in funds, and even in 1917 this was likely not enough to do all of this. However, at some point before her death, Judith had Eugene's remains transferred to the Hillcrest Sparkman Cemetery where she and her husband rest together now.