When was the hadith first gathered together?

The gathering of hadith, the recorded sayings and actions of the Prophet Muhammad, began in earnest during the late 1st century to early 2nd century Hijri (approximately the 8th century CE). Early scholars like Ibn Shuhba and Malik ibn Anas collected and compiled hadith, but it was not until the 9th century CE that the most famous collections, such as Sahih al-Bukhari and Sahih Muslim, were compiled. These collections aimed to authenticate and preserve the traditions of the Prophet for future generations.