Pangeran Muda Hashim

Pangeran or Pengiran is a hereditary honorific prefix for those who have blood ties with the royal family who are married, and can be styled Prince or Princess. The crown price would carry the title Pengiran Muda Mahkota, while sons of the Sultan would carry the title Pengiran Muda.
(This would mean that the textbook is redundant in saying Pangeran Raja as they are both essentially the same title)

Pangeran Muda Hashim is therefore a rightful descendant of throne of Brunei, and was heir-apparent to the throne when he decided to instead let the title go to Sultan Omar Ali Saifuddin II and keep his position as the Bendahara of Brunei (Prime Minister equivalent), which he had served as during the reign of the previous sultan. Pangeran Muda Hashim is also the uncle to Sultan Omar. 

He was sent in 1838 to help Pangeran Indera Mahkota to end the rebellion in the Sarawak region by the sultan. Pangeran Muda Hashim made little progress, and was not on good terms with Indera Mahkota. 

"Around 1834 while Pengiran Indera Mahkota was ruling Sarawak Pengiran Muda Hashim arrived there to try to collect revenue. The reigning Sultan at that time was Sultan Omar Ali Saifuddien II the nephew of Pengiran Muda Hashim.

Pengiran Muda Hashim’s arrival was not personally recieved by Pengiran Indera Mahkota. He only sent his officers to recieve him while he himself waited in his court. This act hurt Pengiran Muda Hashim’s feelings  and he accused Pengiran Indera Mahkota of not respecting him, an uncle of the Sultan. Pengiran Indera Mahkota’s justification was that since he was appointed by the Sultan surely he had the right to do what he thought was right. Since that day the conflict between the two started . . ."

He first sought help from the NNS governor in Singapore, but to no avail. He then proceeded to seek help from James Brooke upon his second arrival at Sarawak. He offered Siniawan and Kuching as well as the Governor of Sarawak position if Brooke managed to stop the rebellion. 

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1. https://en.wikipedia.org/wiki/Malay_styles_and_titles#Brunei
2. http://story-of-sarawak.blogspot.my/2011/12/on-raja-muda-hashim.html
3. Sejarah Malaysia by Ruslan Zainuddin.