[8] In 1922, with composer John Powell, Cox co-founded the Anglo-Saxon Clubs of America, based on Madison Grant's nordicist ideology, in Richmond, Virginia.

The final version passed was more lenient, in that it allowed for classification as "white" even for people with a small amount of Native American blood.

In 1943 when anthropologists Ruth Benedict and Gene Weltfish published their pamphlet "The Races of Mankind" in which they argued that there was no scientific basis for claims of racial superiority or inferiority, Cox wrote a scathing 22-page review, in which he decried the authors as participants in a Jewish and communist conspiracy in favor of "atavistic" and "perverted" miscegenation.

The book argued that race mixing would result in the downfall of "White civilization" and proposed the removal of all people of African descent from the American continent.

The main chapters of the book were examples of historical civilizations that had disappeared or declined, which Cox interpreted as being the result of contact with "Colored races".

The last chapters analyzed the "race problem" in the US, and provided a proposal for a solution, namely, to deport all black people "of breeding Age" to Africa.

[7] The book won positive attention from several important academics and intellectuals in the period, and Cox was invited to Harvard to speak about it by Harry Laughlin the prominent eugenicist.

Laughlin's journal "the Eugenical News" stated that "the removal of Negroes would make Cox a greater savior of his country than George Washington".

In 1924 Cox attended as the only white man, a lecture by Garvey, and after that the two began collaborating, working jointly lobbying legislative measures that would promote the migration of American Blacks to Africa.

[2][4] In 1936 Cox visited Grant who was by then confined to bed by illness, but who nonetheless agreed to create a $10,000 endowment to fund lobby activities in congress for repatriation and deportation legislation.

Grant did not live to make good on his promise, but his friend Wickliffe Draper did it for him and also funded additional printings of Cox' book.

Cox also served as an important adviser to Bilbo, cautioning him to tone down his otherwise often inflammatory speech style and to address his Black allies with some degree of respect.

[4][12][13] The bill failed however, partly due to the outbreak of World War II, which re-focused the attention of national legislation and rendered it impossible to count on the participation of Britain and France in the repatriation efforts.

[15] In his letter to Cox thanking him for the book he described his surprise that an American writer would be advocating the same tenets that he had been taught in the Waffen SS and offered to translate the work into German.

Cox was also a member of the British-based Northern League founded by Roger Pearson, and he was invited to speak at their 1959 conference in the Teutoburg Forest.

[14][17][19][20] In 1960 he wrote a letter to George Lincoln Rockwell the founder of the Virginia-based American Nazi Party sending them the address he gave in the Teutoburger forest meeting, and stating that he was in "fundamental sympathy" with most of their ideas.