Recognized as one of the finest poets in Tagalog,[1] Santos was also renowned with his translations of Rubaiyat of Omar Khayam and of the Philippine National Anthem, and for his use of the ancient Filipino form of poetry known as Tanaga.
He was the father[2] of Ildefonso P. Santos, Jr., the architect who was awarded as national artist for his outstanding achievement in architecture and allied arts.
During his fifth grade, Santos and his friend published a simple periodical of poetry which they sold for one centavo.
His close relationship with his cousin, the poet Leonardo A. Dianzon inspired him to pursue his interest in poetry.
He was then appointed as district superintendent but could not assume the position due to his lack of a college degree.
On July 2, 1954, President Ramon Magsaysay gave him the Award of Merit to Santos for his ‘contribution towards the advancement of Filipino culture in the field of National Language Literature’.
The Panitik ng Kababaihan awarded him the medal of distinction in literature, for being one of the main poets of race.
He was married to Asuncion Paez from Malabon, who bore him eight children, one of which is Ildefonso P. Santos, Jr., the National Artist for Architecture and Visual Arts in 2006.