Short answers, pulled from the story.
Bishop derives from the Greek word epískopos, meaning "overseer" or "supervisor." The English word travelled through Latin episcopus and Old English biscop before reaching its modern form. The Greek term was already in use for several centuries before Christianity adopted it.
Apostolic succession is a direct historical lineage of ordinations traced back to the original Twelve Apostles or Saint Paul. Bishops in Catholic, Eastern Orthodox, Oriental Orthodox, Anglican, and some Lutheran traditions claim it as the basis for their authority to ordain other clergy. The succession passes through the ritual laying on of hands.
Hugh Vermandois became a bishop at age five, making him among the youngest recorded episcopal appointments in church history. Other notable young bishops included Luis Antonio Jaime de Borbón y Farnesio at eight and Guido Ascanio Sforza di Santa Fiora at nine. The First Council of Nicaea set rules about ordination procedures but did not establish a minimum age.
Barbara Harris was ordained a bishop in the United States in 1989, becoming the first woman consecrated as a bishop within Anglicanism. In 2006, Katharine Jefferts Schori became the first woman to serve as presiding bishop of the Episcopal Church.
As Roman authority collapsed in the western empire, bishops absorbed civil administration. After the ninth century, bishops served as archchancellors of the Holy Roman Empire, and the Lord Chancellor of England was almost always a bishop until Henry VIII dismissed Cardinal Thomas Wolsey. The position of Kanclerz in the Polish kingdom was always held by a bishop until the sixteenth century.
Yes. The sitting Bishop of Urgell serves as one of the two Co-Princes of Andorra alongside the President of France. This arrangement began with the Paréage of Andorra in 1278 and was ratified in Andorra's 1993 constitution.