I have read only about a few Cuban Aguiars or de Aguiars on this board. There is still a Calle Aguiar in Habana Vieja, and early registers from Santiago de Cuba (16th century) show that the Aguiar surname was in Cuba nearly 500 years ago. There was a Spanish officer named Aguiar who figured prominently in Cuban history, though the details escape me.
My paternal great-great grandfather is Leopoldo de Aguiar, born in Cuba (in the 1850s or 1860s?), married to Delfina. They had five sons: Mario, Oscar, Luis, Delfin and Guillermo.
My paternal great grandfather is Guillermo de Aguiar, b. 1890 in Cuba, married first to Julia Olazabal and subsequently to Zoila Lozano. Guillermo and Julia had three sons: Guillermo, Rolando (accountant) and Julio (doctor). Julia died at a young age, perhaps during or shortly after childbirth. Guillermo died around 1980 in Havana.
Though I believe I am in contact with all known descendants of Guillermo de Aguiar, I would love to know if anyone is descended from Leopoldo de Aguiar.