He was succeeded by his son, Itzam Kʼan Ahk I, in 639 AD and left behind several monuments, including stelae at Piedras Negras and a large mortuary temple now known as Pyramid R-5.

[3] Kʼinich Yoʼnal Ahk I ascended to the position of ajaw on November 14, 603 AD (9.8.10.6.16 10 Kib 9 Mak in the Long Count), although the exact details surrounding his ascension are unknown.

[2][4] Mayanists Stephen D. Houston and Charles Golden have hypothesized that he founded a new line of rulers at Piedras Negras, possibly following some disaster that dethroned the previous leaders.

[5] Kʼinich Yoʼnal Ahk I systematically razed buildings and monuments at Piedras Negras erected or associated with previous kings, seemingly to thoroughly cleanse the center of any reminder of these "discredited" rulers.

[4] Kʼinich Yoʼnal Ahk I's first was Stela 25, which cemented the use of the "niche" style; these monuments feature the ajaw in a small hollow, seated on an intricately decorated elevated platform, thereby symbolically suggesting that the leader has been lifted into the air.

On Stela 25, Kʼinich Yoʼnal Ahk I is seated on a "jaguar cushion", connected to the ground by a ladder stained with bloody footprints (representing human sacrifice).