A Professor of Magic at Hogwarts - Chapter 547: The Gaunt Ring - (1)

A young man sat on a chair and looked out at the ocean. With one wisp of Spirit Qi, he could point anywhere on this vast and expansive world, pointing at any place that didn’t look right.

Eight years on battlefield and returning in triumph, only then to realize that the important army general is a woman?

Empress Dowager pass an imperial decree, bestowing An Wangye younger brother Xia Yujin as Nanping Junwang and to take the great general as the wife.

In front of the person that kill people like flies, iron mask ruthless of the wife.

Talent-less Jun Wang, in a world of ice and snow fraught with emotional and lake-like tears, request for help, “How to uphold the man principal?”

- Description from Novelupdates

In his past life, Ethan Steele was an ordinary man living in a modern world—working a dead-end job, struggling through the monotony of daily life, and haunted by regrets of missed opportunities.At the age of 23, his life came to a sudden, unexpected end in a car accident. As his consciousness faded into darkness, he was sure it was over.But fate had other plans. In the divine realm, the God of Fate watched over the balance of life and death.Ethan's untimely death was a mistake, an anomaly that diverged from the preordained path of his destiny. It wasn't yet his time to die, and so, the god decided to give him another chance.“You were meant for greater things, Ethan Steele,” the god's voice boomed. “To correct this error, I will reincarnate you in another world—one filled with magic, swords, kingdoms, and adventure. You shall be reborn, but you will not remember your past until the appointed time. There is, however, a... complication.”By divine error, the god accidentally bestowed Ethan with the Harem God System without having any idea about it.This system is a powerful, reality-bending system that would allow him to charm and seduce influential women to build his harem, growing in strength and power with each conquest.“Your memories of Earth will return on your seventh birthday. I hope you enjoy your life here in this world”And with that, Ethan's soul was transported to a new world.

A scientific genius named Thomas Harrier was transmigrated to an imperial prince body after a car accident that took his life. He found out that he is in a world similar to our own with a timeline akin to early twentieth century. The body that he is occupying was the imperial prince of a failing empire who suddenly rose to power after a successful assassination attempt of his father. Unaware that the attack is just the beginning of what is to come. He faces many challenges throughout. Will Thomas Harrier be able to live his second life in peace while running an empire and getting it back to its former glory? Or will he succumb into a conspiracy lurking within the country's borders?

Expect some:

Cold war era techs.

Super battleship with advanced electronics, propulsion, and fire control systems?
Helicopters?
Missiles?
Modern medicines and equipment?
AC-130?
A nuke?
Challenger or Abrams or Leopard?
F-4 Phantom or MIG-21?
Colored TV's.

Everything!!!

PS. Cover not mine, I just found it on google.