Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
bukhari:3161Sahl b. Bakkār > Wuhayb > ʿAmr b. Yaḥyá > ʿAbbās al-Sāʿidī > Abū Ḥumayd al-Sāʿidī

We accompanied the Prophet ﷺ in the Ghazwa of Tabuk and the king of 'Aila presented a white mule and a cloak as a gift to the Prophet. And the Prophet ﷺ wrote to him a peace treaty allowing him to keep authority over his country.  

البخاري:٣١٦١حَدَّثَنَا سَهْلُ بْنُ بَكَّارٍ حَدَّثَنَا وُهَيْبٌ عَنْ عَمْرِو بْنِ يَحْيَى عَنْ عَبَّاسٍ السَّاعِدِيِّ عَنْ أَبِي حُمَيْدٍ السَّاعِدِيِّ قَالَ

غَزَوْنَا مَعَ النَّبِيِّ ﷺ تَبُوكَ وَأَهْدَى مَلِكُ أَيْلَةَ لِلنَّبِيِّ ﷺ بَغْلَةً بَيْضَاءَ وَكَسَاهُ بُرْدًا وَكَتَبَ لَهُ بِبَحْرِهِمْ