Origin and history of was

first-person singular present indicative of be (q.v.); Old English eom "to be, to remain," (Mercian eam, Northumbrian am), from Proto-Germanic *izm(i)-, from PIE *esmi- (source also of Old Norse emi, Gothic im, Hittite esmi, Old Church Slavonic jesmi, Lithuanian esmi), first-person singular form of the root *es- "to be."

In Old English it formed only present tenses, other forms being expressed in the "W-base" (see were, was). This cooperative verb is sometimes referred to by linguists as *es-*wes-. Until the distinction broke down 13c., *es-*wes- tended to express "existence," with beon meaning something closer to "come to be."

Old English am had two plural forms: 1. sind/sindon, sie and 2. earon/aron. The s- form (also used in the subjunctive) fell from English in the early 13c. (though its cousin continues in German sind, the third-person plural of "to be") and was replaced by forms of be, but aron (see are) continued, and as am and be merged it encroached on some uses that previously had belonged to be. By the early 1500s it had established its place in standard English.

Old English beon, beom, bion "be, exist, come to be, become, happen," from Proto-Germanic *biju- "I am, I will be." This "b-root" is from PIE root *bheue- "to be, exist, grow," and in addition to the words in English it yielded the German present first and second person singular (bin, bist, from Old High German bim "I am," bist "thou art"), the Latin perfective tenses of esse (fui "I was," etc.), Old Church Slavonic byti "be," Greek phu- "become," Old Irish bi'u "I am," Lithuanian būti "to be," Russian byt' "to be," etc.

The modern verb to be in its entirety represents the merger of two once-distinct verbs, the "b-root" represented by be and the am/was verb, which was itself a conglomerate. Roger Lass ("Old English") describes the verb as "a collection of semantically related paradigm fragments," while Weekley calls it "an accidental conglomeration from the different Old English dial[ect]s." It is the most irregular verb in Modern English and the most common.

Collective in all Germanic languages, it has eight different forms in Modern English: BE (infinitive, subjunctive, imperative); AM (present 1st person singular); ARE (present 2nd person singular and all plural); IS (present 3rd person singular); WAS (past 1st and 3rd persons singular); WERE (past 2nd person singular, all plural; subjunctive); BEING (progressive & present participle; gerund); BEEN (perfect participle).

The paradigm in Old English was: eom, beo (present 1st person singular); eart, bist (present 2nd person singular); is, bið (present 3rd person singular); sind, sindon, beoð (present plural in all persons); wæs (past 1st and 3rd person singular); wære (past 2nd person singular); wæron (past plural in all persons); wære (singular subjunctive preterit); wæren (plural subjunctive preterit).

The "b-root" had no past tense in Old English, but often served as future tense of am/was. In 13c. it took the place of the infinitive, participle and imperative forms of am/was. Later its plural forms (we beth, ye ben, they be) became standard in Middle English and it made inroads into the singular (I be, thou beest, he beth), but forms of are claimed this turf in the 1500s and replaced be in the plural. For the origin and evolution of the am/was branches of this tangle, see am and was.

That but this blow Might be the be all, and the end all. ["Macbeth" I.vii.5]