Aldmer

The Aldmer (meaning First Ones, First Folk or Elder Folk) were the original race of Mer on Nirn, direct descendants of the Ehlnofey. Much of Tamrielic cultures trace their roots back to the original Aldmeri civilizations.

Altmer legend
In modern lore, the Altmer, also known as High Elves consider themselves the direct descendants of Aldmer and their histories sometimes blur the line between the two. According to Altmer legend, the Aldmer were one of two direct descendants of the Ehnlofey, the other being the proto-race of man. Originally, Aldmer lived on mysterious continent of Aldmeris, with men populating all other continents on Nirn, with Tamriel being an exception. The very existence of Aldmeris is still unknown, though if it exists, it's most likely to be located on the southern or eastern coast of Tamriel. Legends claim that, for unknown reason, Aldmer decided to abandon their home continent and set sail for the nearest habitable region. They landed on Summerset Isles on Tamriel and established elven kingdom there.

Initially, most of the Aldmer remained on Summerset Isles, leaving the rest of Tamriel for primitive beast tribes, which would later evolve into today's Khajiit and Argonians. Some, however, began to explore new found continent. One group traveled by boat up the Niben River, settled on islands in Lake Rumare and built White-Gold Tower, establishing Ayleid empire. Others traveled to Valenwood and evolved into the Bosmer. One more group separated and traveled as far away as possible from the Summerset, those being the Chimer, and settled in Morrowind. According to Chimer history, the Dwemer were already there when Chimer first came, leaving their origins unknown. The Falmer or the Snow Elves' origin is also unknown.

Alternate views
Not everyone agree to Altmeri legends and stories, some even believe Aldmeris being just an idea of unified mer race in Merethic Era, not actually a physical continent. It is possible however, that the Summerset Isles themselves were in fact Aldmeris, from a period before any mer had left to explore and populate Tamriel.

Others believe that mer likely inhabited other continents as humans, and migrated to Tamriel on multiple occasions. The presence of the Dwemer on Tamriel before Chimer's migration and the Falmer's presence strongly support this theory. The idea of Aldmeris and unified Aldmer culture derives from the Altmer's strong belief into their divine destiny and an attempt of returning the golden age of pre-human mer culture.

Humans and Mer
Regardless of how Mer arrived on Tamriel, they were here before human's arrival. The humans melded with the Aldmer and their descendant cultures in upcoming centuries. Some cross-breeding happened, leading to Breton race, but blending of the cultures was much more present. The language of the Aldmer, also called High Elvish, was integrated into human tongue. Though not many people remain that speak the Aldmeri language anymore, it certainly is still present in modern day. Many common words and word fragments, such as the names of mer races themselves, still exist. Some snippets are also occasionally found in books.

By the time of recorded human history, the start of First Era, the Aldmer as an individual race were no longer present on Tamriel. The Bosmer established their true kingdom in Valenwood and, since then, are considered a fully distinct race by the Aldmer. The Dwemer and the Chimer established their kingdoms in Resdayn, and even Orsimer changed to Orcs of modern eras.

Culture
The Aldmeri society was primarily agricultural, with a fully egalitarian government. There wasn't any true kingdom on Tamriel until the reign Bosmeri king that heralded the start of the First Era.

Aldmeri architecture is a wide variety of styles and materials, most of it naturally occurring. The Aldmer weren't above quarrying materials however, as evidenced by coral structure high on top of Summerset Isle's tallest mountains. They were also accomplished engineers, as seen by the giant Crystal Tower that houses the graves of many early Aldmeri settlers. Early Aldmer did not worship gods as humans do, they worshiped their own spirits, living and dead, in practices which they brought from Aldmeris.

On Tamriel however, their culture began to evolve, with more and more of them focusing on their careers and society. At the same time, their religion began to change also, they began to worship the most powerful of their ancestors: the Aedra, specifically Trinimac, Auri-El and Phynaster. This shift in religious focus was the trigger which ultimately led prophet Veloth to take his people, Chimer, over Tamriel, in their new homeland, Morrowind. Another group of Aldmeri elders broke away from the new society and religious look, claiming to be the only true keepers of the Old Ways and named themselves the Psijics. This group would spread across Tamriel, teaching magic to many races and trying to bridge the gap between mortality and divinity. What was left of original Aldmeri culture, would evolve into Altmeri culture, over thousands of years.