Let me bring here some things that may make you think again-
The feats of engineering
This is Kailasa temple, located in Ellora, state of Maharashtra. This was built at time of Krishna I, a ruler of the Rashtrakutas, an empire which back then was ruling a large section of southwestern India and parts of central India.
Looks nice, right?
Now what if I tell you that this entire temple wasn’t actually built like a standard building of today, but rather cut from a single huge rock, what would you think after that?
Note that this entire temple was built around 8th century AD, when there were no modern equipment like excavators, pneumatic drills, cranes and not even those modern-day surveying instruments used by civil engineers of today. All things were done from primitive tools of those days.
The geniuses of those times
Most of us will know this branch of mathematics, right?
One of the very first proponents of trigonometry was a man called Aryabhatta. He is also credited for invention of “zero”, the number without which any modern-day calculation is impossible.

His studies of trigonometry was roughly around the same period when other civilizations like Greeks, Egyptians were studying about this. But Aryabhatta’s methods were comparatively easier than the clumsier Greek versions. Later his works were adopted by Arabs, and his name was there in al-Kwarizmi’s book on algebra.
He was also the first proponent of finding the area of a triangle. One of his famous quotes in Sanskrit goes like
tribhujasya phalaśarīraṃ samadalakoṭī bhujārdhasaṃvargaḥ
Translation:
For a triangle, the result of a perpendicular with the half-side is the area.
Cool, right??
And yeah, he even invented the place-value system, and was a strong proponent of the fact that Sun is at centre of solar system and Earth revolves around it.
Another great man, called Bhaskara II, is known to have something to say about concept of “instantaneous speeds” and concepts of differential calculus, probably half a millennium before scientists like Leibnitz and Newton began their respective works on calculus.
The masters of the oceans
While modern-day India having one of the most powerful blue-water navies is a known fact, but one thing that is often ignored, even by many Indians themselves, is that such a navy wasn’t born in 1947 after British rule ended in India.
Some empires of India, particularly the Chola Empire of southern India, were some of the most experienced historical seafarers that one can know of in the Indian Ocean.
Under Rajendra Chola I, one of the mightiest emperors ever to exist in an Indian empire, the influence of subcontinent spread as far as what are known today as Indonesia, Thailand, Myanmar and Cambodia.

See for yourself, how he fared in his time (Source: Wikipedia)
And yeah, he is respected by our current naval forces too
When the culture of India began going global
Around 319 CE, under the Gupta Empire, a “golden era” began in northern parts of India. This was the period when as some people I mentioned earlier, like Aryabhatt, began his prowess in mathematics and astronomy, when religions of all forms, be it Hinduism, Buddhism or Jainism, was encouraged widely, and when people from regions outside India came to see and understand the culture of the subcontinent.
One particular place built at this time deserves a special mention- Nalanda
Basically a monastery of that period built by Kumaragupta I of the Gupta dynasty, during it’s heydays it served as a university, where people from not just within the empire, but even those from as far as China used to come here to gather understanding about things ranging from religion, culture and science of that period. The library of this place was believed to have been holding text and scriptures unheard of in any other civilization.
But sadly, Nalanda fell in it’s bad days, when one Bakhtiyar Khilji attacked this place, killing the Buddhist monks who ran this place, massacred the students who studied here, and even destroyed that library full of precious texts.
Here is Bakhtiyar Khilji, holding one such text and trying to understand what it says, after he is done massacring the people in university.

Had this guy wasn’t there, the university could have still been intact for far more years, if not to this date.
Strangely enough, much of what we know of what used to happen at Nalanda back then was known from sources not inside but outside India, that too from writings of a pilgrim and traveller who once came to India from China to understand Buddhism. His name is Xaunzang.
Frankly speaking, a large part of ancient Indian history either went lost because of improper record-keeping, or were willfully ignored by some foreigners, who still see India as inhabited by people who cannot win wars against invaders or enemies and are always subjugated to remain subordinate to others. That was one thing that always made sure that parts of history the world never comes to know. Sadly, we have some in India parroting the lines of these foreigners.
But then I also would like to say, no matter how much one lies, it cannot become the truth. One day the truth will stare at them, and they better be ready for that.
As a nation, we got independence from the British in 1947, but our history is way older than that, and we are proud of it.
Still think ancient Indian history is overrated? Think again.
Edit: Someone in comments mentioned if it was great to feel proud if your ancestors were great but your current generation has huge number of problems
I would say- One must be proud of the past,and remember that to create a name for himself/herself in future.
This is the same philosophy that today drives Japan,a nation with one feet in its traditional past and other in modern era.
Basking in glory of past alone never helps,and neither does forgetting your past and living completely in present. You need to have a combination of both.