No, it was not the Chinese who are credited with the invention of rockets in the 11th century, nor the European powers who conquered the world using their military might. It was Hyder Ali and his son Tipu Sultan of the kingdom of Mysore who first used rockets as weapons for serious destruction in their armies towards 1770’s.
These rockets were built in 2 standard sizes and used cast-iron tubes instead of the then customary bamboo or pasteboard used by European armies. This increased their strength, allowed designers to add more power without the fear of the rockets bursting apart and lent additional thrust to the rockets.
The rockets usually consisted of a tube of soft hammered iron about 8 inches (200 mm) long and 1.5 to 3 inches (38 to 76 mm) diameter, closed at one end and strapped to a shaft of bamboo about 4 ft long, some of which had iron points or steel blades bound to them. By attaching these blades to rockets they became very unstable towards the end of their flight causing the blades to spin around like flying scythes, cutting down all in their path. Some rockets also had pierced cylinders, that allowed them to act like incendiaries (bombs designed to start fires).
Tipu even went further and attached a company of rockets to each of their brigades, ultimately a total of about 5000 rocket-carrying troops. The rocket men were trained to launch their rockets at an angle calculated from the diameter of the cylinder and the distance of the target. In addition, wheeled rocket launchers capable of launching five to ten rockets almost simultaneously were used in war.
According to some sources, Tipu Sultan’s rockets could fire at targets as far as 1 mile away. They used these rockets with a devastating effect on the enemy in the Anglo-Mysore wars that they won. According to an eyewitness, one rocket killed as many as 3 soldiers and badly wound others.
Ironically Mysore fell to the British in the fourth Anglo-Mysore war due to a lucky shot that set the rocket store near the walls on fire that breached the fort walls.
The British took hundreds of rockets as spoils of war not so much to use them as to analyse and reverse engineer them, having seen their far more devastating effect compared to their own rockets. William Congreve was in charge of this research and made further improvements that brought uniformity in the quality of rockets and made them even more dependable.
These “Congreve rockets” as they came to be called became famous and were effectively used by the British in the nineteenth century in their various campaigns in Europe, Asia and Africa.
Rockets had many advantages compared to cannons. They could be reloaded easily and quickly compared to cannons. Since they did not generate a recoil, they could be launched from lightweight launchers which increased their mobility manyfold and made them much more preferred compared to bulky cannons.
However even though these rockets were superior to the cannons of their day, they were not without their disadvantages, notably their lack of accuracy. Advances in cannon design ultimately rendered the rockets obsolete and they were hardly used as strategic weapons towards the end of the nineteenth century. They would have to wait for their revival till World War II.