عثمان بن طلحة
Embraced Islam in Madinah alongside Khalid ibn al-Walid and Amr ibn al-As, having left Makkah with Khalid the same night Khalid decided to convert.
Uthman ibn Talhah RA was a man of the Banu Abd al-Dar, the clan that held the keys of the Ka'bah. Before Islam he famously escorted Umm Salamah RA alone from Makkah to Madinah with perfect chivalry. After Hudaybiyyah he accepted Islam, arriving in Madinah with Khalid ibn al-Walid RA and Amr ibn al-As RA. At the Conquest of Makkah in 8 AH the Prophet ﷺ returned the keys of the Ka'bah to him, saying, in Ibn Ishaq's report, "Here is your key; today is a day of good faith"; other reports add that it would stay with his family and link it to the verse on returning trusts [4:58]. The keys have remained with his family ever since.
All 3 events
Converted and made Hijrah before the Conquest of Makkah
لَا يَسْتَوِي مِنكُم مَّنْ أَنفَقَ مِن قَبْلِ الْفَتْحِ وَقَاتَلَ ۚ أُولَٰئِكَ أَعْظَمُ دَرَجَةً مِّنَ الَّذِينَ أَنفَقُوا مِن بَعْدُ وَقَاتَلُوا
“Those of you who donated and fought before the victory (i.e., the Conquest of Makkah) are unparalleled. They are far greater in rank than those who donated and fought afterwards.”
Cited regarding Uthman ibn Talha's conversion shortly before the Conquest of Makkah.
إِنَّ اللَّهَ يَأْمُرُكُمْ أَن تُؤَدُّوا الْأَمَانَاتِ إِلَىٰ أَهْلِهَا
“Indeed, Allah commands you to return trusts to their rightful owners.”
Cited by the Prophet ﷺ as the basis for returning the key of the Ka'bah to Uthman ibn Talha.