I'm very interested in Special Forces history, specifically the SBS/SAS and wondered if anyone here knew if they were the first modern day 'Special forces' and if not then who were?

Any insights into this greatly appreciated.

From Wikpedia:

During World War II in 1940 the British Commandos were formed following Winston Churchill's call for "specially trained troops of the hunter class, who can develop a reign of terror down the enemy coast." The Commandos were selected from volunteers among existing servicemen and went on to spawn a number of other specialist units including the Long Range Desert Group, the Special Air Service, the Special Boat Service and the Small Scale Raiding Force of the Special Operations Executive.
In the Burma Campaign, the Chindits, whose long range penetration groups were trained to operate from bases deep behind Japanese lines, contained commandos (King's Regiment (Liverpool), 142 Commando Company) and Gurkhas. Their jungle expertise, which would play an important part in many British special forces operations post war, was learnt, at a great cost in lives, in the jungles of Burma fighting the Japanese.
In mid-1942, the United States formed the Rangers. The United States and Canada also formed a sabotage ski brigade for operations in Norway who became known as the Devil's Brigade during their eventual service in Italy. Merrill's Marauders were modelled on the Chindits and took part in similar operations in Burma.

If you research commandos, rangers, and special forces you may find quite a bit of information. Also, researching the SOE may help you find information as well regarding some of the tactics used. British Commandos were taught their knife fighting skills by W.E. Fairbairn, who was also Chief Instructor at Camp X in Canada.

Hope this helps. Michelle