The term Mughal architecture is generally used to denote the building style that flourished in northern and central India under the patronage of the Mughal emperors from the mid-16th to the late 17th century. The monuments and gardens constructed by the Mughals saw strong influences of Persian, Indian, and various provincial styles.
Babur's Char Bagh Scheme
Although Babur ruled only for a brief period, he left his indelible signature on all that was to follow in Mughal architecture. He gave medieval architecture a new direction and revolutionized the whole art of building. Mughal architecture after Babur was presented through the formal char bagh (four-part garden that emulates the Garden of Paradise in Islamic tradition) plan wherein the ethereal effect of the Persian garden, complete with its water channels, stone tanks and water chutes, formed an integral part of the whole scheme.
Akbar's National Style
While Babur charted the course of the new architecture, it was Akbar who took it to higher levels. The Humayun's tomb at Delhi, built by Akbar, is considered the precursor of this national style that culminated with the construction of the Taj at Agra. The style is a perfect amalgamation of Persian and Hindu influences: while the char bagh scheme continued to hold its distinct pre-eminence, the Hindu influences can be seen in the use of beam-and-post (trabeate) building method and the associated stone-carved ornamentation. Recourse to jali (filigree), lavishly used in Mughal buildings, also points out to the influence of the latter school.
Jahangir's Iranian Style
Jahangir's marriage to Nur Jahan in 1611 brought Iranian influence to the Mughal court. The importance attached to minute details of Persian embroidery work, the use of calligraphic lines from the Qur'an and the use of typical Persian flowers like narcissus, iris and tulip (instead of the lotus and lily used earlier) in paintings are distinctive features of this architectural style. In addition, the style sought to do away with red sandstone, which hitherto constituted the chief building material in Akbar's time. Instead, Jahangir made large-scale use of white marble in building the upper storey of Akbar's tomb at Sikandra. His wife, Nur Jahan, followed this up by building the entire tomb of Itmad-ud-daulah (also Mirza Ghiyas Beg; Nur Jahan's father) in white marble.
Shah Jahan's Golden Age
Mughal architecture reached its zenith during the reign of emperor Shah Jahan (1628-58), its crowning achievement being the magnificent Taj Mahal. The Persian elements that were introduced during his predecessor's reign achieved fruition, and indigenous elements were now brought under restraint. Among the characteristic features of Shah Jahan's style, the bulbous dome, the engrailed arch and the elaborate use of chhatris (cenotaphs) are the most prominent. The trabeate (horizontal) method of building in Akbar's time was replaced by the arcuate (curved) method to give an impression of grandeur and magnificence to the edifice. The construction material was predominantly white marble though red sandstone with a heavy overcoat of white shell plaster was also used.