Engineering is one of the oldest professions in the world. Around 2550 BC, Imhotep, the first documented engineer, built a famous stepped pyramid of King Zoser located at Saqqarah.
The first engineers were military engineers, combining military and civil skills. During periods of conflict the engineers made and used instruments of war such as catapults, battering rams, towers, and ramps to aid in attacking their enemies' forts & encampments and also to defend their own. During the periods of peace, they were involved in many military and civil activities such as building fortifications for defence against further attacks, roads, bridges, aqueducts, canals and cathedrals. The construction and hydraulics techniques used by the medieval engineers in China, Japan, India and other regions of the Far East were far more sophisticated than those of the medieval European engineers.
Civil engineering is the oldest of the main disciplines of engineering. The first engineering school, the National School of Bridges and Highways in France, was opened in 1747. John Smeaton was the first person to actually call himself a "Civil Engineer". These civil engineers built all types of structures, designed water-supply and sewer systems, designed railroads and highways, and planned cities. In 1828 the world's first engineering society came into being, the Institution of Civil Engineers in England.
Mechanical engineering was the second branch of engineering to emerge in the last part of the 1700s. The invention of the steam engine was the starting point for the Industrial Revolution. All types of machinery were being developed now and so a new kind of engineer, one dealing with tools and machines, was born. Mechanical engineers received formal recognition in 1847 with the founding of the Institution of Mechanical Engineers in England.
Knowledge of electricity grew slowly during the 1800s: the original electric cell was invented by Alessandro Volta in 1800, the Gramme dynamo and electric motor were invented in 1872, the transistor and the vacuum tube appeared by the mid 1900s and by the end of the 1900s electrical and electronics engineers outnumbered all the other types of engineers in the world.
In the 1800's, industry started using more and more chemical processes in many areas such as metallurgy, food production and textiles. At the end of the 19th century, the increased use of chemicals in the manufacturing industry eventually created a new industry, an industry whose main function was the production of chemicals. The new chemical engineer was involved in the design and operation of these new chemical producing plants.
Around 1900, the term "Chemical Engineer" was being used, but it wasn't until the development of the petroleum industry that chemical engineering became recognized as a unique engineering discipline.