So I am planning to short story based around Haqqislam profiles, but I do not own any of the book and know very little of their fluff. Is it possible to be a soldier of Haqqislam without being a muslim of the Haaqislamite Faith? If this question is a little culturally insensitive I apologize but I just am trying to gain some knowledge of for one of my characters.
I wouldn't think so – not every troop in their army has the "Religious" tag, I would only assume that the non-religious units are either religiously unaffiliated or practice the Haqqislam religion more casually. Haqq also employs a lot of merc units which for sure are not religiously affiliated
They have followers "of the book" (christianity and judaism) in their society, as well as followers of new islam - so I don't see why not. The background mentions christians and jews get charged an extra "faith tax" but otherwise are left to themselves and freely mingle in society.
The "Religious" skill isn't literally "does someone believe in God," but rather "Is someone primarily religiously motivated in their fighting." So almost all personnel in the Haqq armed forces are going to be little-r religious, but they're professional soldiers, not crazy people like Ghazi. I actually would think that, based on the fact that Christians and Jews in Haqqislam pay an extra tax, they *don't* serve in the Haqqislamite armed forces, since historically part of the justification for that tax was that they were not required to serve in the military like Muslim men were.
I would assume that there are also plenty of secular folks who may nominally belong to the faith but don't put a particularly large amount of personal weight on it. You see that sort of attitude in most real-world religious communities, and I see no reason it wouldn't be present on Bourak as well.
In Daedalus' Fall Haqqislam background, the Masada Regiment is presented as "a regular unit of the Sword of Allah composed solely of Jews".
In the background I believe all followers of the Haqqislamite religion are required to pay an extra tax that goes towards the maintainance of the Haqqislamite religious infrastructure. If you aren't, you pay a tax that goes towards other social projects. Basically there is a ring fenced tax that is allocated based on whether you are a registered Muslim I think. Most are, many aren't, they are by no means 2nd class citizens.
Well, as for the tax... it is, actually, an old thing in classic Islam. The followers of Islam paid their religious tax, zakat if memory serves me, that went to the community to be spent on charity projects (and upkeep of religious institutuions). The followers of other tolerated religions ("people of the Book", - in classic Islam, Christians & Jews of any variety, as well as Zaratustrians) paid a different, somewhat higher tax that went for other purposes. Now, keep in mind this solution is not unknown in modern societies. As far as I'm familiar with today's German regulations, you pay a "church tax" that state collects from you and transfers to the religion of your choice (i.e. you declare yourself as a Roman Catholic, it goes to the Roman Catholic Church in Germany. You change your mind next year and declare yourself a follower of a different legally recognized religion, you get your tax declaration corrected and your money from there on goes to your new chosen church). Should you declare yourself to be not a follower of any religion, you are exempt from the "church tax", but instead you have to pay a different tax the state is to spend on social projects. Note: I'm not German, anyone German and better oriented in the matter please do correct me one that. ...actually the social tax" is a bit lower than the "church tax", which made many Polish immigrants choose that option to save a few euros. All fine and dandy, but then after a while they've noticed the elephant in the rom: you don't pay, so you aren't registered as a member of the local parish. You're not a Chrisitan, you see - you have declaed yourself as such yourself, right? In your tax declaration, haven't you? Well, makes getting a church wedding or baptising your newborn kid a mite difficult... ...and that's even before there was the talk about German parishes informing your home parish in Polnad that you've left the Church, and a such should be written off the lsit in your home town or village (which is, well, a big issue in some communities!)... So, in my eyes, the Haqq don't fall too far from that idea. As for not being a Haqqislamite - they are expressedly welcoming other People of the Book. I guess you wouldn't be catching too much flak being an agnostic or even atheist, if you don't make it into an issue. Y'know, "Bob over there is a mite weird fellow, if you catch my drift, but he's an okay neightbour apart from that. Keeping to himself and not making a fuss about it. I guess we could invite him to an iftar one Ramadan evening next month, I think he should be getting more time among the neightbourhood community".
And I think it is important to note that New Islam of Haqqislam is quite different from that of todays islamic states. It is far more tolerant and more like a mindset than a religion.* Scientific and medical knowledge, as well as education in general is seen as main virtues. (* Or like the early islam until 700. Also note that there is a difference between Islam and Faith, so not every moslem needs to be a true believer.)
As the others noticed before, Haqqislam tend toward the first years of the Islam the period historians call "the Golden Era of Islam", preceding all the various fractions that came to be with the later expansions. To answer in short: yes, it is possible. It does not matter as long as you follow a muslim ruler who apply the Shari'a. Most of the nomad tribes in northen Africa were not muslim but were use as mercenaries and later converted to Islam. Another fact that might help you is that you were not muslim but wanted to serve (as a civil administator for example) you could find a well-being/reputed family/clan and be a servant to it: you got their surname and every action was reflected upon the family's reputation. If you served well you might become a full fledge member of the community and not a "2nd class" citizen. This was due because of the origin of the muslims, who were nomads and lacked the expertise to rule an empire. To circumvent this problem (and the fact that the rulers had to be muslim) they employed the services of cristians and jews from the cities of the eastern roman empire as aides. Called Jizya, granted the followers of those monoteist religions that were revealed before the advent of Islam protection from external threats, freedom to practice their religion and personal freedom. It also excused them from military service and the payment of the Zakat [the tax only for muslims to help the ones in need(widows, orphans, ect...)]. PS Just to be sure, know that there might be some imprecisations and/or error and for that I'm sorry since it has passed quite some time from when I studied this subject