Dhimmi is a category of non-muslim who has agreed to pay jizya and follow Islamic laws, except for certain purely religious matters such as practicing their own religion in private and consumption of wine etc.
Not all non-muslims are dhimmis, rather they must fulfill two conditions:
- they must be followers of a religion who is allowed to be dhimmi according to Islamic law.
- they must agree to become dhimmi by surrendering to Islamic rule and following the treaty that they have made. If they have not made a treaty they are not dhimmi and if their treaty is violated then they no longer remain dhimmis.
Whether or not a follower of some religion can be Dhimmis depends on the scope of the verses and ahadith:
فاقتلوا المشركين حيث وجدتموهم ... فإن تابوا وأقاموا الصلاة وآتوا الزكاة فخلوا سبيلهم
Kill the polytheists wherever you find them ... But if they should repent, establish prayer, and give zakah, let them [go] on their way.
— Quran 9:5
قاتلوا الذين لا يؤمنون بالله ولا باليوم الآخر ولا يحرمون ما حرم الله ورسوله ولا يدينون دين الحق من الذين أوتوا الكتاب حتى يعطوا الجزية عن يد وهم صاغرون
Fight those who do not believe in Allah or in the Last Day and who do not consider unlawful what Allah and His Messenger have made unlawful and who do not adopt the religion of truth from those who were given the Scripture - [fight] until they give the jizyah willingly while they are humbled.
— Quran 9:29
فأمرنا نبينا رسول ربنا صلى الله عليه وسلم أن نقاتلكم حتى تعبدوا الله وحده أو تؤدوا الجزية
Our Prophet, the Messenger of our Lord, has ordered us to fight you till you worship Allah Alone or give Jizyah (i.e. tribute)
— Bukhari
As the first verse only allows for two choices: accept Islam or be fought.
Whereas the second verse and hadith allows for a third choice: pay jizya.
As for Zoroastrians, there is disagreement on whether they are People of the Book. Most of the Ahl al-Sunnah do not consider them to be People of the Book, however they do allow for them to be Dhimmis. The reason being:
There is a chance that they could have been people of the book at some point in time
9:29 can be interpreted to include those who do not believe even if they are not people of the book
The sunnah proves that can be made dhimmis:
أخذ رسول الله صلى الله عليه وسلم الجزية من مجوس البحرين وأخذها عمر من فارس وأخذها عثمان من الفرس
The Messenger of Allah (ﷺ) took the Jizyah from the Zoroastrians of Bahrain, and 'Umar took it in Persia, and 'Uthman took it from the Persians.
— Jami at-Tirmidhi, Bukhari
Ref:
اتفق الفقهاء على جواز عقد الذمة لأهل الكتاب والمجوس، كما اتفقوا على عدم جوازه للمرتد. أما فيما عدا ذلك فقد اختلفوا
The jurists are agreed that it is permitted to make a pact of Dhimma with the People of the Book and the Zoroastrians and they are also agreed that it is not permitted to make it with an apostate. As for those other than them there is disagreement on it.
— Mawsoo’ah al-Fiqhiyyah