He was born in Corsicanna, Texas. child of Ema Dellums and his Step Father William Henry Dellums.
He attended the public schools in Texas, graduating from Jackson High School .
He planned to move to San Fransisco because he thought it was the most ideal place for a Negro to live in 1923; He also wanted to be a lawyer and learned that the University of California had the best law school. But instead he end up moving to West Oakland because someone insured him not to many blacks can make it in San Fran. and he realized he wouldnt make enough to even attend school.
He was a room stewards , basically a maid taking care of all the passengers needs and taking care of the rooms also. He hated working on tthe ship.
Dellums became one of the porters where he earned $2 per day. You might get $60; but the odds were ten to one that you'd never get $60 while you were a young porter. Later on he was fired because of being a union activist.
He was the first African American man to be elected in the Executive and Arbitration Committee for the Central Labor Council of Alameda County. Cottrell joined N.A.A.C.P and had been a active member since 1927. He dedicated many years to this organization and was later on elected President of the same branch the membership was under 400 and by the end of his presidency it was over 3,000.
Cottrell always wanted to be treated equally and paid the correct amount that was due for his hardwork. Later on he came across a Brotherhood that was willing to help and felt the sameway. He joined the Brotherhood when was first established by A. Philip Randolph.
The Local Official was just established in the Brotherhood and Cottrell was qualified.
Being apart of the union he was later fired from his current job which was being a porter at the Pullman Company. So he became a full-time official at the Brotherhood.
The Brotherhood became a part of the labor movement and advocated that Negroes join the labor unions and encouraged them to join. Many of them thought that they couldn't join unions because the belief that the AF of L discriminated against Negroes. With Randolph and his wonderful voice, his great oratorical ability, his wonderful, unbelievable knowledge, his mastery of the English language, he had no peer. People at the AF of L convention who fought against him were so far beneath him that they were conscious of it themselves. By Randolph being the greatest attraction in the race, the Brotherhood won support of Negroes and general recognition.Out of the conferences Randolph held with Green and other members of the Executive Council, they decided to accept thirteen federal local charters from the AF of L in order to become an actual affiliated part of it. They didn't affiliate all of their local unions. The Brotherhood just picked out thirteen. They had an unwritten agreement with them that the Brotherhood wouldn't even operate like normal federal locals; they would just continue to operate as they were.They would operate as a national union with Randolph at the head of it and without any interference from them.
This was when the International was set up in 1929, he was elected Vice President, a position he held until October, 1968. Soon after that date, Mr. A. Philip Randolph, founder, organizer and first International President, retired, and upon his nomination, Mr. Dellums was elected his successor.
The second convention was held in St. Louis where Cottrell tried to help a man Roy Lancster hold his position as the Secretary-Treasurer of the Brotherhood but later on realizing it waws no use. They won the first election but Randolph later approached Cottrell about this situation and said no matter how hard they fight Roy Lancster was going to be withdrawl because many people believe that Roy was a liar and a theif and was not benefiting the Brotherhood.
Was elected to the Executive and Arbitration Board in Alameda County's Central Labor Council.
They refused to recognize the Brotherhoods existence for ten years. Then when they were forced to deal with the issue, the Brotherhood proposed a working agreement and it took two more years, mostly with a federal mediator, to get an agreement out of the Pullman Company. The Pullman Company wasn't at all happy when the time came to sign.The agreement was signed on August 25, 1937, the twelfth anniversary of the union.
Mr. Randolp and Mr. Dellums and many others that were apart of the union that was fighting for equal rights and treated fairly was met also the march on Washington resulted in F. D. Roosevelt issued a executive order eliminating discrimination in defense industries and the government itself.
Cottrell was choice elected of the chairmanship of the N.A.A.C.P in 1944 . Cottrell held his position until he refused to serve any longer in 1967.
Governor Brown asked him to accept an appointment to the Commission. Cottrell later accepted a two-year term in 1959, a full term in 1961, and a second full term in 1965. At this timeGovernor appointed him Chairman of the Commission.
He passed in Oakland in 1989