From Wiktionary and Etomology Online
you (pron.) Old English eow, dative and accusative plural of þu (see thou), objective case of ge, “ye” (see ye), from Proto-Germanic *juz-, *iwwiz (cognates: Old Norse yor, Old Saxon iu, Old Frisian iuwe, Middle Dutch, Dutch u, Old High German iu, iuwih, German euch), from PIE *yu, second person (plural) pronoun.
Pronunciation of you and the nominative form ye gradually merged from 14c.; the distinction between them passed out of general usage by 1600. Widespread use of French in England after 12c. gave English you the same association as French vous, and it began to drive out singular nominative thou, originally as a sign of respect (similar to the “royal we”) when addressing superiors, then equals and strangers, and ultimately (by c.1575) becoming the general form of address. Through 13c. English also retained a dual pronoun ink “you two; your two selves; each other.”
Because of its pronunciation, ewe and its homophone you form one of only two homophone pairs in modern English that share no letters.
The other pair is ‘I’ and “eye”, with “aye” also for some dialects,
and then there’s Yew
ewe (n.) Old English eowu, fem. of eow “sheep,” from Proto-Germanic *awi, genitive *awjoz (cognates: Old Saxon ewi, Old Frisian ei, Middle Dutch ooge, Dutch ooi, Old High German ouwi “sheep,” Gothic aweþi “flock of sheep”), from PIE *owi- (cognates: Sanskrit avih, Greek ois, Latin ovis, Lithuanian avis “sheep,” Old Church Slavonic ovica “ewe,” Old Irish oi “sheep,” Welsh ewig “hind”).
The decapitated “i”
Why decapitate “i”; leave “I” headless?
I /aɪ/ is the first-person singular nominative case personal pronoun in Modern English. It is used to refer to one’s self and is capitalized, although other pronouns, such as he or she, are not capitalized. In Australian English, British English and Irish English, me can refer to someone’s possessions (see archaic and non-standard forms of English personal pronouns).
English I originates from Old English (OE) ic. Its predecessor ic had in turn originated from the continuation of Proto-Germanic ik, and ek; ek was attested in the Elder Futhark inscriptions (in some cases notably showing the variant eka; see also ek erilaz). Linguists assume ik to have developed from the unstressed variant of ek. Variants of ic were used in various English dialects up until the 1600s
aye (interj.) “assent,” 1570s, of unknown origin, perhaps a variant of I, meaning “I assent;” or an alteration of Middle English yai “yes” (see yea), or from aye (adv.) “always, ever.”
aye (adv.) “always, ever,” c.1200, from Old Norse ei “ever” (cognate with Old English a “always, ever”), from PIE *aiw- “vital force, life, long life, eternity” (cognates: Greek aion “age, eternity,” Latin aevum “space of time;” see eon).