Sultan Pakaru-d-Din was succeeded by Kibad Sahriyal, who possessed many of the good qualities of his father and ruled with firmness and success. In the meantime the power of Spain in Mindanao had revived and her forces became active again. Kibad maintained friendly relations with Spain and signed a treaty with her in 1794, in which he promised not to enter into any treaty or agreement with another power. Like his father he had many wives and concubines and begot many children, chief among whom are Sultan Kawasa and Alamansa Sul-Karnayn. Kawasa succeeded his father and maintained the dignity of his office and the prosperity of his sultanate. He is often called Anwaru-d-Din (lights of religion) and Amiru-l-Umara (the prince of the princes). He had many children, chief of whom was Intirinu or Amirul. Alamansa died at Dansalan. He had many children, two of whom were Raja Twa, and Datu Dakula, the prince of Sibugay. Raja Twa begot Untung and Perti. The nation looked to Raja Twa to succeed Sultan Kawasa, but he died before his uncle, and the sultanate fell to his young son, Untung. Intirinu was rejected for family reasons and Datu Dakula was set aside to give representation to the favorite house of Twa. Untung was known as Sultan Sakandar Qudratu-l-Lah (Alexander, the power of God). He was also surnamed Jamalu-l-A'lam (A'zham), which means "greatest beauty." Qudrat the Second was the last sultan who observed all the customs and rites of the sultanate. He was young when he assumed power, and his reign marked the beginning of the downfall of the sultanate and the actual occupation by Spain of the Rio Grande Valley. In the treaty of 1837 he submitted to the sovereignty of Spain and accepted the subordinate title of Feudatory King of Tamontaka. Spain appointed his successor and prohibited his people from invading any territory west of Point Flechas. She regulated the licensing of boats sailing beyond Zamboanga and erected a trading house at Paygwan, at the mouth of the Rio Grande. In 1843 Datu Dakula ceded to Spain the west coast of the Zamboanga peninsula, promised to aid in suppressing slavery, and acknowledged Spanish protection. In 1845 Sultan Qudrat confirmed the treaty of 1837, with a more definite submission, and allowed the establishment of a Spanish trading house at Cotabato. This aggression on the part of Spain was prompted by her increased strength and an additional naval revival. Steamboats and improved firearms ended Moro aggression and solved the Moro question. In 1851 Polloc was occupied and was made a naval station. In 1857 Spanish boats advanced as far up as Tambao and drew up a treaty with the sultan of Talakuku in which he acknowledged his surrender and his submission to the authority of Spain. In 1861 camps were established at Cotabato, Libungan, Tambao, Taviran, and Tamontaka.