On May 27, I joined 15,000 British Ahmadi Muslims to celebrate the most important milestone in the Muslim world for decades: the 100th anniversary of the return of the Khilafat or Caliphate.

The word "Caliphate" has a tarnished image in Britain, frequently associated with images of blood, brutality and a totalitarian Islamic theocracy. The rise of extremist groups which call for the re-establishment of a worldwide Islamic state have helped heighten such fears.

But for Ahmadis and many other Muslims, the Caliph is a spiritual not a worldly office. "Khalifa" means literally successor or guardian and thus the Caliph is charged with continuing the message and mission of the Prophet Muhammad, educating and reminding Muslims everywhere of their responsibilities to God, towards the rights of others, and the need for developing good morals.

Following the Prophet’s death, the first Caliphs played a key role in the spread of Islam. Chosen by the Prophet’s most trusted companions, they were peaceful, pious and humble. Yes, they had an impact on world politics - the second Caliph Hadhrat 'Umar successfully foiled a threat from the Roman and Persian empires - but their role was essentially spiritual.

This divinely guided Caliphate ended abruptly after the assassination of Hadhrat Ali, the Prophet’s fourth successor, in the late seventh century because of tensions and disputes inside and outside the Muslim community. Self-styled caliphs followed but not without further bitter divisions among Muslims.

Despite those differences Muslims have recognised and campaigned for the need for unity under one leader again who would represent a central spiritual authority. While it seems unrealistic to expect all Muslims to unanimously accept one supreme figure, in my community, the Ahmadi Muslims, we believe that after an absence of almost 1,400 years Khilafat was finally re-established in Islam by Hadhrat (His Holiness) Mirza Ghulam Ahmad, a 19th century Prophet, who claimed under divine instruction to fulfil the major prophecies contained in Islamic and other sacred texts regarding a world reformer who would unite humanity. His death in 1908 was followed by an unbroken chain of Khalifas, all elected by eminent members of the Ahmadiyya community.

The Khalifas have constantly motivated their followers to excel in both spiritual and secular disciplines. These followers have included Sir Muhammad Zafrullah Khan, a former President of the UN Assembly, and Professor Abdus Salam KBE, the first Muslim Nobel Laureate for Physics.

In the past 100 years, the five Khalifas have spearheaded an Islamic revival, spreading the Ahmadi Muslim faith to 190 countries and a membership numbering tens of millions. In Britain, there are 18,000 Ahmadi Muslims who follow the blessed guidance of the present Khalifa, Hadhrat Mirza Masroor Ahmad.

Waqar Ahmad Ahmedi is the regional coordinator for the Ahmadiyya Muslim Youth Association in the Midlands. He can be contacted at midlands@khuddam.org.uk. The official website of the Ahmadiyya Muslim Community is www.alislam.org