Alexandra David-Neel provides fantastic accounts of the daily life of tibetans at the beginning of the XXth century.

http://alexandra-david-neel.com/9000Accueilanglais.90.html

Eventhough she was essentially attracted to the spiritual side of the Tibetan people, she describes a life of extreme frugality but deep serenity that seems to span pretty much all layers of the population.

I particularly recommend "My journey to Lhasa", published in 1927, which is perhaps more factual. She was neither an anthropologist nor a historian, more a traveler/explorer. At the time, Lhasa was forbidden to foreigners, like Timbuktu had been in the XIXth century.

Hi there! Great question. Like any society, "Tibetan people" is a broad term. The Plateau was not a unified nation-state like we may imagine it. Heinrich Harrer's "Seven Years in Tibet" is a great place to start looking for an answer to your question as it covers Tibet in the '40s and '50s just prior to HH's flight to India. Harrer experiences life in Kyirong, southern Tsang practically on the Nepali border, and has limited experiences with pastoral villagers in the Yarlung Valley, Khampa herders, and cosmopolitan Lhasaps.

u/thbb seems to hit the nail on the head. Life was very frugal and spiritual for most people. Illiteracy was high because only monks needed to read or write. Languages differed from region to region, and in many places from village to village. For example, the Dalai Lama's family spoke Amdowa, not High Tibetan which he later learned when his religious training began. High Tibetan (the religious language) is very different from "Low" Tibetan which is the vernacular spoken around Lhasa and Tsang. And then there are places like Kyirong that have their own language even though the language doesn't extend beyond their own village.

Tibetan cuisine is centered around meat and barley so society was divided largely between settled barley cultivators and nomadic yak herders. Lhasa was the only thing approaching a cosmopolitan area in Tibetan society (which was nothing compared to what counts as a city, or even a town, in neighboring India or China). Aside from farming or herding, religious life was always a huge option and there are episodes of history where a "monk tax" was instituted (I would need to look up when Tibet had these, I don't know if they were in the 20th Century). The "monk tax" typically expected families to send every third son to the monastery to ordain. Since no one could force you to ordain, it was often expected that those sons would return home when they reached the age of majority. Many non-third sons joined the monastery voluntarily, while many third sons stayed on their own.

It's generally regarded (various scholars of the Himalayas agree. Helena Norberg-Hodge is huge on this point, Heinrich Harrer tends to agree, but less so, and Bhutanese sources are quick to note it) that women had higher positions than their contemporaries in Europe (and astronomically so than their contemporaries in India and China). Yet Harrer also notes that with the family he stayed with in Lhasa, the matriarch of the family was focused on increasing women's rights and power in the country.

What aspects about life in pre-1950 Tibet are you particularly interested? I can be far more specific if I know what you're interested in.