Was Columbus a Spaniard?

There is significant evidence suggesting Columbus was, in fact, a Spaniard even though legend holds that he was from Genoa, Italy.

- Correspondences with his brother were in Spanish. (If they were Italian, wouldn't they have written in Italian?)
- Correspondences with his bankers in Genoa, Italy were in Spanish. (If Columbus were Italian, why would he communicate with his Italian bankers in Spanish?)
- Columbus never claimed to be from Genoa, and in fact was always vague about where he was from. Although the myth said he went to sea as a young adult, his own writings claimed he went to sea as a boy.
- There is evidence of a merchant family named Colon (the accepted Spanish version of Columbus) which was on the wrong end of some internal political strife in Spain, so disguising his origins would be in his self-interest when approaching the royal court for backing of his expeditions.