He did not begin keeping a diary until adulthood, and what survived spoke little of his youth. He is thought to have had a normal childhood, with his magical abilities emerging in adolescence.
Nathan's abilities as a mage were recognized early and he held a prominent station within the family by his mid-teens. It is believed he was married to a first or second cousin by age 15, solidifying his standing in the family.
What records survive also indicate that he may have disappeared for a few years, possibly between 16 and 18, but returned to lead the family and to build the first Mage Tower
The Searlins practiced polygamy, then outlawed in the city-state, and Nathan may have taken as many as 7 wives; all first, second, or third cousins of his own. Surviving fragments of his diaries indicate that he only upheld this custom because it maintained his position within the family. He had several children by each of these marriages, and married them off prestigiously (one of his daughters was even married to Draco).
Nathan would rule over Asysias from High Tower for nearly 30 years. From there, records of his later life become extremely spotty. It is known that he left High Tower before its fall, but how long is not well-established. Some claim he disappeared in secret with his close friend and confidant Gideon Rikart, and that the Searlin family kept his disappearance a secret until the fall of High Tower. Others believe he may have died with the rest of the Searlins when the city was sacked and the tower taken. A volume of The Circle of Seven was found in his possessions.
No two sources agree on what exactly Nathan looked like. In many historical accounts, he is often confused with Gideon Rikart, thus making it difficult to pin down a physical description of him as well. However, all sources agree on one thing unanamously: Nathan had very piercing green eyes, shared by all the most powerful mages of his line.
Nathan was a prodigious chronicler, and is known to have kept a journal throughout his entire life. He most likely made entries at least every day, often multiple times. Though no one has ever been able to determine exactly how, several dozen volumes of his journals, covering a good portion of his life at High Tower, eventually made their way to the Library of Arindell.
Popular theory holds that when he fled High Tower, Nathan loaded three ships with his personal library and many artifacts of magic that he had collected, and eventually brought their contents to the library. However, no other volumes besides the journals have been positively identified as having belonged to Nathan or having been at High Tower.
The positively-identified journals cover about four years in Nathan's early twenties, and sporadic periods throughout the rest of his life.