Your answer here would be the emancipation proclamation Announced by Abraham lincoln
President Abraham Lincoln<span> issued the Emancipation Proclamation on January 1, 1863, as the nation approached its third year of bloody civil war. The proclamation declared "that all persons held as slaves" within the rebellious states "are, and henceforward shall be free." </span>
B.
For those that could not write (So most), they carried a seal around either on a necklace or otherwise that they could use to stamp with ink to signify 'signing' something.
The answer for this would be the individuals on the island would all appear very alike to individually or each other, and they may demonstrate uncharacteristically high incidences or manifestation of traits that are unusual in the universal human population.
