▁Jes uit ▁mission ary ▁accounts , ▁and ▁observations ▁from ▁visit ing ▁scient ists ▁like ▁Otto ▁von ▁Kot z eb ue ▁and ▁Louis ▁de ▁Fre yc inet . ▁ ▁An cient ▁Cham or ro ▁society ▁ ▁When ▁Europe ans ▁first ▁arrived ▁on ▁Gu am , ▁Cham or ro ▁society ▁roughly ▁fell ▁into ▁three ▁classes : ▁m ata o ▁( upper ▁class ), ▁ach a ot ▁( middle ▁class ), ▁and ▁man a ' ch ang ▁( lower ▁class ). ▁The ▁m ata o ▁were ▁located ▁in ▁the ▁coast al ▁villages , ▁which ▁meant ▁they ▁had ▁the ▁best ▁access ▁to ▁fish ing ▁grounds ▁while ▁the ▁man a ' ch ang ▁were ▁located ▁in ▁the ▁interior ▁of ▁the ▁island . ▁M ata o ▁and ▁man a ' ch ang ▁rarely ▁communic ated ▁with ▁each ▁other , ▁and ▁m ata o ▁often ▁used ▁ach a ot ▁as ▁a ▁go - between . ▁ ▁There ▁were ▁also ▁" m ak han as " ▁( sh am ans ) ▁and ▁" sur u han us " ▁( her b ▁do ctors ), ▁sk illed ▁in ▁he aling ▁and ▁medicine . Bel ief ▁in ▁spirits ▁of ▁ancient ▁Cham or ros ▁called ▁Ta ota o ▁Mon a ▁still ▁pers ists ▁as ▁rem nant ▁of ▁pre - Europe an ▁society . ▁Early ▁European ▁expl or ers ▁noted ▁the ▁Cham or ros ' ▁fast ▁sail ing ▁vessels ▁used ▁for ▁trad ing ▁with ▁other ▁islands ▁of ▁Mic ron esia . ▁ ▁Lat te ▁The ▁" lat te ▁stones " ▁familiar ▁to ▁Gu am ▁residents