Funny enough, that’s actually not true. July and August were originally named Quintilis and Sextilis (5th month and 6th month respectively) and were both renamed by the Senate well after Julius and Augustus died to honor them.

January and February were (re-added) later by Pompilius to sync the Roman calendar with a lunar year (364 days).

Unless you meant Pompilius, but he added those months for totally legitimate reasons.