▁meas les , ▁the ▁Ch um ash ▁decl ined ▁in ▁numbers ▁until , ▁in ▁ 1 8 2 2 , ▁the ▁last ▁of ▁the ▁Ch um ash ▁left ▁the ▁island ▁for ▁main land ▁California ▁miss ions . ▁ ▁The ▁name ▁of ▁Santa ▁Cruz ▁for ▁the ▁island ▁came ▁about ▁when ▁Gas par ▁de ▁Port ola ▁expedition ▁visited ▁the ▁Ch um ash ▁village ▁X ax as ▁on ▁the ▁island . ▁ ▁The ▁Ch um ash ▁on ▁the ▁next ▁day ▁returned ▁a ▁staff , ▁to pped ▁by ▁an ▁iron ▁cross , ▁which ▁had ▁been ▁in ad vert ently ▁left ▁behind ▁by ▁the ▁Spanish . ▁ ▁Hence , ▁the ▁name ▁La ▁Is la ▁de ▁la ▁Santa ▁Cruz ▁( is land ▁of ▁the ▁holy ▁cross ) ▁appeared ▁on ▁their ▁expl oration ▁map ▁of ▁ 1 7 7 0 . ▁ ▁George ▁V ancouver ▁used ▁the ▁same ▁name ▁on ▁his ▁ 1 7 9 3 ▁map . ▁ ▁With ▁Mexico ' s ▁independence ▁from ▁Spain ▁in ▁ 1 8 2 1 , ▁the ▁Mexican ▁government ▁assert ed ▁its ▁control ▁over ▁Al ta ▁California . ▁In ▁an ▁effort ▁to ▁increase ▁the ▁Mexican ▁presence , ▁the ▁government ▁began ▁sending ▁conv icted ▁crim inals ▁to ▁California ▁in ▁ 1 8 3 0 . ▁Ar ound ▁ 8 0 ▁prisoners ▁were ▁sent ▁to ▁Santa ▁Barbara ▁where , ▁upon ▁arrival , ▁ 3 1 ▁incor rig ibles ▁were ▁sent ▁to ▁Santa ▁Cruz ▁Island . ▁They ▁lived ▁for ▁a ▁short ▁time ▁in ▁an ▁area ▁now ▁known ▁as ▁Pr ison ers ' ▁Har bor ▁before ▁esc