While the same trick would work for Bulgaria, the rest of the world would consider it aggressive expansion, especially if we also annexed the Black Sea littoral as planned, and the fertile Danube plain as well.
South of Romania there were fewer Romanians still alive, but plenty of Aromanians, desperately trying to hang on their language, traditions and sometimes religion.
However, I did have a Greek wife, who was also the daughter of the Greek King. And this marriage was proposed and accepted on the basis of an alliance versus Bulgaria, and perhaps Serbia.
Meeting with both of my wives was a bit awkward at first, since Zizi Lambrino wasn't well-liked in my Royal Household for some reason. But needs must and all.
"Mircea, you are my son. And you also deserve to be King." I spoke in a friendly tone, and patted my firstborn boy on his shoulder. He did look more normal the the other one, since he wasn't procreated with a cousin like Helen of Greece.
Zizi perked up at the news, while Helen frowned. "What country?" she asked in a glacial voice.
"Bulgaria, of course. However, I will need Greece to mobilize and step a kilometer North with their army, or there will be no pie sharing with Greece otherwise." I demanded with a cold voice as well.
"Black Sea access?" Helen asked in a cunning voice.
"For that, the Greek Army would need to take Sofia by themselves. If they do that, no problem. But otherwise..." I answered with a shrug. The Greek Army was far worse than my own army, having no tanks or airplanes, but they did have a decent fleet.
Three months later, Greece mobilized and manned their Northern border with Bulgaria, forcing half of the Bulgarian army to forcefully redeploy to match the Greeks.
Not so fun being squashed between two enemies now, Bulgaria?
The third armor division was still in training and using the old French F-17 tanks, but they were enough to slowly push along the shore towards Varna and Burgas, while backed by several infantry divisions. The F-17 might be old and slow, but they only had to keep pace with foot infantry so it kinda worked.
Meanwhile, the main armor push came across the Danube under our fleet's protective guns, with floating pontoon bridges and two armored divisions covered by airplanes.
Barely a third of the Bulgarian Army was available to fight our armored divisions, and they were promptly encircled and left in the care of the follow-up infantry divisions.
Two extra motorized divisions followed after the tanks, in their rush towards Sofia, and while lacking tanks they still had truck-towed artillery and anti-air.
The Bulgarian lightning war lasted 7 days only, although we cheated by using the Greeks as a decoy. But still, we will write the history afterwards, so it was fine.
The first flying ace was born in this war while covering the Danube crossing, while several Legion flyers sacrificed themselves to cripple the Bulgarian Navy, small as it was. It turns out, a 12 inch shell with wings and a pilot can do a lot of damage. Who knew, right?
This tale has been unlawfully lifted from Royal Road; report any instances of this story if found elsewhere.
The dead kamikaze were promptly Sanctified as Angels of the Legion, and their families were given a post-mortem medal called Legion of Merit with Angel Wings.
People loved it too, making a big show in newspapers and speeches about our holy clay and the blood of martyrs.
And I think Zizi might be pregnant again, she was quite happy to see me again, especially after our son became King.
The Greeks were not too pleased since the price of one mile was 50000 dead and the ire of the British, but what can I do? I only asked for one kilometer, nobody forced them to walk more. At this time, their government was still a republic, since they blamed the monarchy for their loss in the Turk-Greek war of 1922.
I had an opportunity now, being a King myself and not a loser like their former King.
Making war upon Greece was possible, I even had a game tab for it, but it would be difficult to argue for it, since the players of the Great Game were not AI sub-routines, but real people.
However, I could become their King, since my wife was Greek and the daughter of their former King. And I was a victorious King too. That mattered a lot.
Setting the Network on the task, to obtain support for a Romanian King of Greece that is, and promising them Albania and Constantinople.
I turned my attention to the research again.
While a bit earlier than in the former timeline, the IAR plant began making (crappy) propeller fighters, while the Fokker plant nearby produced the first real plane, even sooner than the BF 109.
Better cameras and even color movies could be obtained, and an early radar model was installed on the flagship of the navy for field studies.
The first submarine we build sank a week later, so it wasn't all good.
The further work on the Dacian Wall along the Dniester continued as planned, basically one level of fort per year. Once we reached level 10, and Tier 5 Anti-Air defense, I could spit at the Soviets and dare them to come.
Czechoslovakia was getting a bit scared of Germany by now, and building their own version of a fortress wall towards the West. And ignoring the border towards Hungary for some reason. Oh well, I was allowed an easy win sometimes, right?
As for Yugoslavia, they were being eyed by all the powers in the region, mostly by Italy though.
Their armed force were kinda crap, and they had a lot of internal problems with numerous enemy ethnicities, including some Hungarians in Voivodina and Romanians along the Danube and Timoc Valley. Yeah, Yugoslavia was a fake and failed state, and was doomed to shatter sooner or later. Might as well give it a push myself.
By the time Bulgaria was fully occupied and pacified, Greece wisely decided to throw in with the Ever-Victorious King, and nominated me as their ruler.
It helped I was an Orthodox King too, something rather rare after the Romanovs got whacked by the communists.
Taking Albania didn't take a large war, basically pushing the nearest divisions to the Adriatic Sea at a walk, and being cheered as the second coming of Alexander the Great by the locals. Italy was furious, of course, but I couldn't care less. Albania made silk, and that was quite a bonus.
Before Britain could get too angry and send a fleet to the Adriatic, I decided to pacify the Italians by offering to share Yugoslavia with them. That seemed to work.
Three months later, Italian, Greek, Bulgarian, Hungarian and Romanian troops invaded from all sides, each with the promise of more clay for blood.
Turns out, taking Belgrade and Nis and a few big cities was not enough to make Yugoslavia quit. I should have known better, Elite difficulty wasn't that easy.
Luckily, there were plenty of Bulgarian and Hungarian soldiers to take the brunt of the guerilla fighting, while the Greeks bogged down in Muntenegro and the Italians almost got thrown into the sea before their fleet arrived to bombard the enemy.
While the war ragged on, the Iron Legion marched into the occupied lands to pacify the rebels, being seen as Angels by Romanians and as Devils by everyone else.
Nothing that wouldn't happen anyways, sooner or later.
About a year later, and a million dead, Yugoslavia was basically a ruin and my army was out of tanks and trucks.
But hey, at least Romania was bigger now, and we had 5 more puppets in the Balkans: Serbia, Montenegro, Bosnia(with Dubrovnik), Albania (with Kosovo) and Voivodina.
The Italians would regret not forming Slovenia and Croatia as puppets though. While the guns fell silent in our lands, the Italians are still fighting for their Mare Nostrum dream.