Venancio Roberto was a resident of HagÃÂ¥tña, Guam who briefly seized the office of Commissioner of Guam from December 31, 1898, to January 2, 1899, before his rule was declared illegitimate by Lieutenant Commander Vincendon Cottman of . In 1898, Roberto overthrew José Sisto, and was put in office by a military junta composed of a number of district leaders from around the island; only two days later, the United States Navy decided that Sisto held the legitimate claim to the office, despite Roberto's generally more pro-United States leanings. The coalition, which included local leader Father José Palomo y Torres and former governor Francisco Portusach MartÃÂnez, stepped aside until the ownership of Guam could be determined.