ye

old or quaintly archaic way of writing the, in which the -y- is a 16c. graphic alteration of þ, an Old English character (generally called "thorn," originally a Germanic rune; see th-) that represented the "hard" -th- sound at the beginning of the. Early printers, whose types were founded on the continent, did not have a þ, so they substituted y as the letter that looked most like it. But in such usages it was not pronounced "y." Ye for the (and yt for that) continued in manuscripts through 18c. Revived 19c. as a deliberate antiquarianism; the Ye Olde _____ construction was being mocked by 1896.

2nd nominative singular personal pronoun, Old English þu, from Proto-Germanic *thu (cf. Old Frisian thu, Middle Dutch and Middle Low German du, Old High German and German du, Old Norse þu, Gothic þu), from PIE *tu-, second person singular pronoun (cf. Latin tu, Irish tu, Welsh ti, Greek su, Lithuanian tu, Old Church Slavonic ty, Sanskrit twa-m).

Superseded in Middle English by plural form you (from a different root), but retained in certain dialects (e.g. Philadelphia Quakers). The plural at first was used in addressing superior individuals, later also (to err on the side of propriety) strangers, and ultimately all equals. By c.1450 the use of thou to address inferiors gave it a tinge of insult unless addressed by parents to children, or intimates to one another. Hence the verb meaning "to use 'thou' to a person" (mid-15c.).

Avaunt, caitiff, dost thou thou me! I am come of good kin, I tell thee! ["Hickscorner," c.1530]

A brief history of the second person pronoun in English can be found here.