After Imam al-Mahdi establishes his rule, will there be any oppressors remaining in perow?

After Imam al-Mahdi establishes his rule, will there be any oppressors remaining in perow?

The character trait of the universal rule of Imam al-Mahdi will be the worldwide maintenance of peace, security, justice, and the annihilation of the foundations of corruption, decadence, oppression, and crime. This has been the main purpose of all the prophets, but with the difference that the success of the latter and their successors following them was not as decisive. Nevertheless, establishing worldwide peace and security has always constituted one of their promises. And so the unpolluted souls of mankind at large, ever since the beginning of human history, have been waiting for the time when those promises would be realized. Now since Allah, His messengers, and their infallible successors do not breach their promises, they would not raise the hopes of people without a good reason. This means that this promise will certainly be realized and that a just government will be established, consisting of the aforementioned characteristics.

This promise is so vital and real that its realization can be considered the rationale behind the creation of humankind, a promise that once realized will lead to the unity of the whole of humankind under the banner of Tawhid and, by Allah’s Mercy, the uprooting of disbelief, polytheism, and hypocrisy from amongst them. (11:118&123)

The narrations that express this are numerous. For instance, it has been recorded that Imam Hasan b. Ali al-Askari (peace be upon him) told his son, [Mahdi]: “It is as though I see you when Allah’s support has been sent upon you, relief (faraj) has been achieved, your magnificence and greatness has risen… It is at this moment that the rule of truth will dawn and the darkness of evil will vanish from the scene of existence. Through your hands, Allah will break the oppressors’ backs, will reinstate the religious sacraments, will enlighten the horizons of the world, and will establish calm and peace throughout the world. Your enemies will be disgraced and your friends esteemed and victorious. Not even a single oppressor, criminal, rebellious denier, encroaching enemy, spiteful opponent will remain on the face of earth, for whoever trusts in Allah, He will provide him sufficient support. Verily, Allah fulfils His wish and executes His definitive promise and will. Verily Allah has set a plan for everything.”