Teodoro Kalaw was one of the most outstanding writers and historians of the Philippines.
Kalaw specialized in the collection of original books and documents, which became
the basis for much of his historical research.
He became the youngest editor of El Renacimiento, an extreme nationalist newspaper.
His editorials staunchly defended the national interest and he became an arch-critic
of the American colonial regime.
Kalaw became director of the National Library, writing in his spare time historical
essays. Historical writings between the 1900s to 1940 were so dominated by him, that
the Philippines' historian Teodoro Agoncillo considered this period as the "Age of
Kalaw." Kalaw's literary output was so prolific that later generations of Filipinos
consider him the father of Philippine libraries.