Imber, described (in 1904) as "our own . . . erratic meteor on the firmament of literature, sublime genius, and lover of good red wine," is without a doubt best known for penning the poem Tikvosenu, which was adapted as the Hovevei Tzion anthem and in a slightly revised form became the national anthem of Israel, Hatikva. But here he took an interesting foray into historical scholarship, not quite making the grade.
If you didn't read it, basically he is objecting to Joseph Jacobs' then-recent contention that the Passover poem was about 700 years old. Imber notes that it is in Aramaic, and therefore it must be Babylonian. Not only that, he claims that there had been a "Babylonian liturgy" entirely in Aramaic. He compares Chad Gadya to Yekum Purkan, also in Aramaic, and also Babylonian. The problem he does not contend with is that Yekum Purkan doesn't appear in Babylonian sources like the Seder Rav Amram or Rav Saadya and was never a part of the liturgy of Sephardic or other Babylonian-influnced Jewries. It is Ashkenazic all the way, appearing in the Machzor Vitry. He also compares it with Kaddish, another remnant of an alleged Aramaic Babylonian liturgy. He surmises that there was also a Babylonian Aramaic Haggadah, and the surviving remnants are the opening prayer Keha Lachma Anya and the closer Chad Gadya.
In fairness it should be pointed out that this was 1889 and still a relatively primitive time in historical liturgical study. To be sure, the sources existed in libraries, and the greatest scholars accessed them and did serious research, but for a layman with scholarly pretensions there wasn't much to go on. The Machzor Vitry was first published in 1893. The Cairo Geniza was still a secret. But the Seder Rav Amram had already been published. There isn't even an attempt at analysis of the language.
That said, according to the most recent scholarship the Yekum Purkan prayer is a type of prayer, which was recited in Babylonia, as well as elsewhere. Still this is a far cry from the theory that it is a remnant of an entire Aramaic liturgy. Imber forgets that Aramaic was the language of Babylonian Jewry, but it is also a Jewish literary language all over the world. Akdamus Milin anyone?
See my old post So Where did Chad Gadya Come from Anyway?. I of course didn't reach any brilliant conclusion, but summarizing what was still known - in 2010 - I showed that although it first shows up in 15th century texts which we know of, one source in the 18th century claimed that the song was in a manuscript in the Bet Midrash of the Rokeach. Unfortunately we don't know anything about the date of that manuscript. I showed that at the latest it probably existed in 1406, but also may have been a century or two older. Thus we can say that Chad Gadya almost definitely existed in 1406 and for some time earlier. It is probably not 700 years old, and thus it is more recent than Joseph Jacobs surmised, and Imber's guess isn't even in the right millenium.
Imber wrote several other such articles for the Jewish Standard, and also proposed that Sheidim - demons - in the Talmud are really just small, unseen organisms that wreak medical havoc on humans.