Throughout much of its conceptual development, Quenya had two distinct roots for the verb to be: the root √NĀ functioning mainly as a copula in “to be” expressions like Elrondo Elda ná “Elrond is an Elf” or Aracorno halla ná “Aragorn is tall”, versus a distinct root used mainly for existential statements such as Eru ëa “God exists”. The copula-root was established very early as √NĀ, but the existential-root varied considerably.
The earliest version of the existential root was ᴱ√Ō “be, exist” from the Qenya Lexicon of the 1910s (QL/69). By the 1920s it seems this root has changed to ᴱ√Ī as it appeared in Early Qenya words lists from that period (PE16/140), and the verb for “to be” in the contemporaneous Early Qenya Grammar was ᴱQ. e- or i (PE14/51, 57).
A similar root ᴹ√YĒ or ᴹ√I appeared in The Etymologies of the 1930s, albeit with no derivatives (EtyAC/YE). It was most likely the basis for the so-called “stative” suffix ᴹQ. -ie seen in the contemporaneous Fíriel’s Song (LR/72). The root ᴹ√YE was also mentioned in both the first and second versions of the Tengwesta Qenderinwa from 1937 (TQ1: PE18/60) and around 1950 (TQ2: PE18/84), though in the latter it was rejected (PE18/84 note #69). This root is reflected in the use of ᴹQ. ye- in the Quenya Verbal System (QVS) from 1948 (PE22/107, 115, 117, 119-120), but this verb was rejected and replaced towards the end of that document by a new verb ᴹQ. ea- (PE22/122-124 and PE22/123 note #130). The rejection of ye- “to be” may be due to the introduction of Q. yén for the Elvish long year, as suggested by Christopher Gilson (PE22/86).
In QVS, the new verb ea- was derived from a primitive ✱eʒe or ✱eñe (PE22/122); the root ᴹ√EƷ “be” had already been mentioned in Outline of Phonetic Development (OP1) from the late 1930s, indicating Tolkien had been considering this form for some time. In 1948 QVS, Tolkien said:
> The primary sense of this verb was “to exist, to have being, to be found, extant, in the real world”. But it was often weakened to the copula, in statements of identity or predication. This however in classical Quenya was limited mainly to the past and future (PE22/123).
Thus in 1948 Tolkien started the process of establishing ea- as primarily an existential verb. A few years later, Tolkien mentioned the root √EÑ “be” in the Outline of Phonology (OP2) from the early 1950s (PE19/96) and he described √EÑ more fully in verbal notes from 1969 where he said:
> Stem of verb “exist” (have being in primary world of history) was √EŊE, distinct from √NA joining adjs./nouns/pronouns in statements (or wishes) asserting (or desiring) a thing to have a certain quality, or to be the same as another (PE22/147).
Thus the conceptual development of this root seems to have roughly been √Ō (1910s) >> √YĒ/Ī (1920s) >> √EƷ (late 1940s) >> √EÑ (early 1950s). This is an oversimplification however, in that √EƷ appeared in The Etymologies of the 1930s and Tolkien may have been considering it much earlier. Furthermore, the role of √EÑ as primarily as existential root (vs. copula √NĀ) was only firmly established in Tolkien’s later writings. When the root was √YĒ/Ī in the 1920s through 1940s, it seems the verbs ᴱQ. e- and ᴹQ. ye- were used for both existential statements and as a copula, and in this period √NĀ (though mentioned) was rarely used and may have been out of favor.