The phrase 'あの日 人類は思い出した' carries a weight that's hard to capture in a single translation. From what I've seen in official materials, it's most commonly rendered as 'On that day, mankind remembered' in English contexts. This particular line originates from '進撃の巨人' ('Attack on Titan'), where it marks a pivotal moment in the narrative. The official English subtitles and manga translations consistently use this version, which maintains the ominous tone while flowing naturally in English.
What fascinates me is how this translation preserves the original Japanese structure while making it accessible. The choice of 'mankind' instead of 'humanity' adds a slightly more archaic, dramatic feel that matches the series' atmosphere. Some fan translations experiment with variations like 'recalled' instead of 'remembered,' but the official version has stuck for good reason - it perfectly encapsulates that chilling realization the characters experience.