This was revealed at Minā during the Farewell Pilgrimage, hence it is considered Medinese: it was the last sūra to be revealed; it consists of 3 verses.

When the help of God, for His Prophet (s), against his enemies, comes together with victory, the victory over Mecca,

and you see people entering God’s religion, that is to say, Islam, in throngs, in large droves, after they had been entering one by one — this was after the conquest of Mecca, when the Arabs from all corners of the land came to him willingly [in obedience to his command] —

then glorify with praise of your Lord, that is, continuously praising Him, and seek forgiveness from Him; for verily He is ever ready to relent. The Prophet (s), after this sūra had been revealed, would frequently repeat the words subhāna’Llāhi wa bi-hamdihi, ‘Glory and praise be to God’, and astaghfiru’Llāha wa-atūbu ilayhi, ‘I seek forgiveness from God and I repent to Him’; with [the revelation of] this [final sūra] he realised that his end was near. The victory over Mecca was in Ramadān of year 8; the Prophet (s) passed away in Rabī‘ I of the year 10.