Deodato Arellano was a Filipino patriot who was among the founders of the Katipunan that started the Philippine Revolution against Spain. He also served as the secretary of the La Liga Filipina, founded by Jose Rizal.

Their family adapted the surname Arellano after the Claveria decree of 1849 requiring Filipinos who met a certain criteria to pick a new name from a catálogo alfabético de apellidos. After receiving his degree in bookkeeping, he worked as assistant clerk at the arsenal of the colonial army in Manila.

Reference:

• "Deodato Arellano". Wikipedia.org. http://bit.ly/X4NLA2. Date published: 2 February 2013. Date accessed: 14 Feb 2013.
• "Supreme Council (Kataastaasang Sangunian". Katipunan activists in Manila, 1892-96. http://bit.ly/Y8zCPI. Date accessed: 13 Feb 2013