"chronicle of events year-by-year," 1560s, from Latin annales libri "chronicles, yearlies," literally "yearly books," plural of noun use of annalis "pertaining to a year," from annus "year" (see annual (adj.)). In the early Roman republic, the Pontifex Maximus each year would record public events on tablets called Annales Maximi, hence Latin historical works were called annales.
<a href="https://www.etymonline.com/word/annal">Etymology of annal by etymonline</a>
Harper, D. (n.d.). Etymology of annal. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/annal