Instead of continuing in the Beards thread, I figured this topic is worthy of its own thread.
Here is some information that I copied from the Avodah section of Aish Das:
The upsheren custom of Hassidim, which at first glance seems like some
venerable and ancient custom no good Jew would oppose, is actually
a controversial new custom which they picked up from certain middle
eastern Jews called 'mustarbim', which was and is rejected by certain
great gedolim and communities.
Although proponents attempt to attach it to the mitzvoh of orlah (fruit
from newly planted trees prohibited for first three years, etc.) (Vayikra
19:23-25), early mekoros (Rabbinic sources) (e.g. Rokeach 296, Daas
Zikeinim Mibaalei Tosfos on Vayikra 19:23), as well as later ones
(e.g. Eliyohu Rabbah 17:3, Ohr Hachaim on Vayikra 19:23), omit any mention
of such an custom, even, while at the same time, they mention approvingly
an old minhag to start a young boy in Torah learning at that time. There
is also no mention of it in very detailed, lengthy and comprehensive
works, such as the Shulchan Oruch and siddur of Rav Yaakov Emden.
The attempt to place the posthumous imprimatur of the Ar'i on it via
a tale told of him allegedly having given his son a haircut on lag
ba'omer is not as simple as it may appear initially as well. It comes
from an account by Rav Chaim Vital, but the language in the account is
not clear and it's not certain if it refers to the Ar"i or someone else
who was with him. Also, it it happened before the Ar"i reached his great
stature in Kabbalah, which occurred later in his life, and therefore
he may have not held of it then, as per his shita, based on kabbalah,
not to cut hair for the whole sefira period, including lag ba'omer.
In Ashkenazic communities of Lita, Germany, Hungary (Oberland), etc.,
the upsheren custom was not accepted, and the young boys were given
haircuts at a young age (sometimes when just a few months or even weeks
old), without any special event/celebration around it. Similarly, it was
not recognized in Sepharadic communities in Amsterdam, Hamburg, London
at all, as it was not done in Spain. In certain Moroccan communities,
the hair was cut at the age of nine months. In the famed 'sheva kehillos'
of Hungary, they cut the hair at one year of age. In Yemen too, the hair
was cut with no special celebration.
The renowned Brisker Rav, Rav Velvel Soloveitchik (HaGRY"Z), when he
came to Eretz Yisroel and was brought a child for such hair cutting,
declined, saying 'ich bin nisht kein sherer' (I am not a barber). His
position was explained with the following logic. Even if someone has long
hair, he is not oveir (doesn't transgress) the prohibition of 'lo sakifu
peas roshchem' (not to cut off sideburns / peiyos). So when you give
a child his first haircut, even his hair is lengthy, you are not doing
a mitzvoh - so it is just a regular haircut - so if you need a barber,
go find a barber - I am a Rav, not a barber.
The Steipler Gaon, Rav Yaakov Yisroel Kanievsky z"l, also refused to
go along with it. It is told (in sefer 'orchos Rabbeinu', by his talmid
Rav Avrohom Horowitz, volume one, p.233) that he would drive away ( ! )
people who came to him with three year old boys asking him to cut their
hair and was very angry about it ( ! ).
A very significant consideration is also the question if there is a
problem of 'chukos hagoyim' with the custom. While we don't generally
see it now (in western countries at least), the fact is that in certain
eastern cultures (e.g. arab and hindu / Indian) a great deal was/is
made of a son's first haircut and it was accompanied by a significant
celebration. It seems that those Jews who started the custom Jews
lived among such gentiles. So there is a concern that it may well have
originated in gentile practice. The discussion now underway [squeak's note: this reference to the Indian sheitel crisis (heh heh) dates the content of this post but in no way detracts from its value] re a serious
concern of avoda zara (idolatry) with human hair wigs from India made
from hair Indian women there cut off at Hindu temples as part of giving
thanks to their deities shows how real this concern is - even in our
modern era - and certainly in past years.
We also have clear traditions and sources from the gemara on down
that talk of cutting a young boy's hair before he is three years old -
in some cases much before - with no mention of such contradicting any
'upsheren'/'chalakah' type custom. The gemara (Moed Kotton 14a) says
that a youngster born with long hair can be given a haircut right
away. The Shita Mikubetzes (Nedorim 30a) says that the hair of young
boys was regularly and often cut. In Eastern Europe, non-Hassidic Jews
customarily cut a son's hair when he started to speak without waiting
until three years of age. In the family of the 'Steipler Gaon', hair
of his grandchildren was cut at two years of age, without any special
event being made of it / surrounding it.
Even among Hassidim, not all do the same thing. IIRC, Chassidei Gur
and Skvira, cut the hair at two years of age - not three - which seems
difficult to understand if it is based on orloh.
Among others (e.g. Sephardic Jews in Yerusholayim), the haircutting came
even later - at five years of age.
The above is from various sources, but mostly from an excellent survey
of the matter in 'Shorshei Minhag Ashkenaz', volume III, by Rav Binyomin
Shlomo Hamburger, Mochon Moreshes Ashkenaz, Bnei Brak, 5762.
And this was annotated by Micha Berger as follows:
This is actually VERY related to the issues of sheitlach.
Hindus celebrate a child's first haircut in a ceremony called Mundan. Here's
This is a ceremony in which a male child gets his first haircut done. It
usually takes place when he is three, five or seven years of age. It is
customary to conduct this ceremony at the shrine of the family god or
in the temple of lord shiva. Clipped hair are placed along with some
cow dung, milk and two coins wrapped in a piece of cloth and later on
offered at the temple or the shrine of kulja (family god/goddess) or
a holy river. The ceremony is performed to receive blessings for the
child. The cutting ceremony is first of all started by the maternal
uncle of the child and is carried on by a barber. The maternal uncle
bears all the expenses of the ceremony.
Now, let's discuss this topic without denegrating either the minhag to upsherin or not to upsherin. Pertinent facts aside, the minhag of upsherin is now a minhag yisroel and therefore should be discussed with appropriate resepect for the minhag.