Short answers, pulled from the story.
Old English, also called Anglo-Saxon or Englisc, is the earliest attested form of the English language, spoken in England and southern and eastern Scotland during the Early Middle Ages. Scholar Albert Baugh dates it from 450 to 1150, spanning roughly 700 years from the Anglo-Saxon settlement of Britain to the aftermath of the Norman Conquest.
The word Englisc means "pertaining to the Angles," one of the Germanic tribes who settled in Britain in the 5th century. By the 9th century the name was applied to all Old English speakers regardless of whether they claimed Angle, Saxon, or Jutish ancestry.
The four main dialects are Mercian, Northumbrian, Kentish, and West Saxon. Mercian and Northumbrian are grouped together as Anglian. West Saxon became the literary and governmental standard under Alfred the Great, but the standard forms of Modern English descended from Mercian, and Scots from Northumbrian.
Cædmon's Hymn, composed between 658 and 680, is the oldest surviving work of Old English literature. It was not written down until the early 8th century. Cædmon served as a lay brother in the monastery at Whitby and is the earliest English poet known by name.
Scandinavian settlers in the Danelaw from the late 9th century brought Old Norse into close contact with Old English. Because the two languages shared similar word bodies but differed in inflectional endings, those endings eroded through daily use, pushing English from a synthetic, inflection-heavy language toward a more analytic word-order-based structure. This grammatical simplification is widely attributed to Norse influence.
Old English was first written in runes using the futhorc, a set derived from the 24-character Germanic elder futhark and extended by additional characters for Anglo-Saxon vowel sounds. From around the 8th century, Irish Christian missionaries introduced a Latin-based script, supplemented by four additional letters: ash (ae), eth (th), thorn, and wynn. Unlike modern English, Old English spelling had a largely predictable sound-to-letter correspondence with almost no silent letters.