The Cross-Time Engineer

Series of books written by Leo Frankowski in the nineties. The plot involves a Polish Engineer from the late 20th century named Conrad Sschwartz (who later is called "Conrad Stargard"), who is thrown into the mid-thirteenth century because he gets into his cousin's time machine while completely hammered. Once he comes to terms with where and when he is, Conrad realizes he only has ten years to turn Medieval European Poland into an industrial superpower, or else the Mongols will completely overrun the country and murder everyone.

So he gets to work on that right away...

These books are known for being extremely technically written, and the author as much as admitted that mainly Engineers and military buffs would like his works. In addition, the author has written "others, mostly Feminists, Liberals, and Homosexuals, seem to instinctively hate my guts", so beware of that if you plan to read these books.

": People who can afford parchment to wipe their butts are richer than anyone in this century!"
 * Alternate History/Alternate History Wank: Poland becomes "Conrad Stargard's Army Empire"...
 * Alternative Number System: The new civilization Conrad starts up in Medieval Europe uses base 12 mathematics, as it is more convenient for division (being a multiple of 2, 3, and 4).
 * Author Appeal: Frankly, the series has enough appeals to fit into every single category on this page.
 * It was bad enough the final books of the series are self-published. The books didn't sell and the publisher got sick of his Self Insert Author Avatar.
 * Automaton Horses: Conrad receives a bio-engineered horse that is super competent, speedy, enduring, strong, etc., etc., etc.
 * Beastly Bloodsports: One of Conrad Stargard's first controversial acts is to euthanize a bear that's being used for bear-baiting.
 * Creator Provincialism: Poland features very prominently in the series.
 * The Engineer: Conrad.
 * Fish Out of Temporal Water: The entire premise of the book series.
 * Giving Radio to the Romans: Pretty much describes the main thrust of the entire series.  Conrad has ten years to get Poland powerful enough to repel the Mongols.
 * Hungry Jungle: Conrad faces this when attempting to explore Africa. After the massive death incurred by both the explorers and the natives, Conrad vows to do no more exploration until he'd found a solution.
 * Mundane Luxury: Father Ignacy is able to prove to that Conrad is from the future simply by showing him several pieces of toilet paper Conrad had given him.


 * One-Man Industrial Revolution: The series is all about this trope.
 * Our Time Travel Is Different: Conrad's cousin can send stuff back in time to help him, but it only goes one-way and thus, Conrad can't simply go back to the future.
 * This is because he was discovered only after having been stranded for ten years, so that event was set in stone. Nothing was known about his financial state, so it was justifiable to drop a chest of gold and silver in his path.
 * Portal Cut: The series employs Portal Cuts for many purposes, including embedding a super-thin layer of diamond in the center of a sword to make the edge.
 * Pure Is Not Good: Conrad reflects on his pastor's words that one with a pure heart has the strength of ten men. He realizes that it could be pure anything; pure love or pure hate, pure greed or even pure evil.
 * Time Travel Escape: Conrad tells his time-traveling cousin Tom that he (Conrad) saw Tom get killed by a Mongol spearman in 1241. Tom's response was "Hmmm... I guess I'll avoid going to Poland in 1241, then." Thus performing this trope on himself.
 * Trapped in the Past: Somewhat obvious trope.
 * Vanity Publishing: The first few books were published by Baen Books, but the later novels are entirely self published.
 * Victim Falls For Rapist: The third book of the series, The Radiant Warrior, has Piotr, who has been in love with Krystyana for most of his life; she pointedly does not return his feelings, and only seems to be interested in the hero of the series. He resolves this problem by becoming a knight, which in this series means that he has the absolute right to have sex with any unmarried lowborn woman, and promptly carries her off and rapes her, ignoring her pleas and protests, with a cheering crowd outside the bedroom door. But not to worry; the sex was apparently awesome, and in the morning Krystyana is all smiles and ready to get married.