Robert Silverberg 
Longest Way Home 

For more than a thousand years, Homeworld has been unchanged: the Great Houses rule and peace between them is enforced by unbreakable webs of kinship. The Folk accept what the system offers them – stability, prosperity and peace – and the Indigenes are placid. Then, on one night of rebellion everything changes, as the Folk overthrow the Great Houses. Joseph, the young son of one Great House is visiting another and survives the violence, but his home is ten thousand miles away and communications and transport have been destroyed. For all he knows his family may have been wiped out but his only hope lies in making that ten thousand mile trek across a world turned strange and hostile.To succeed, he must set aside all his old beliefs and assumptions and learn the truth about the world he lives in.