It is said that no battle plan survives first contact with the enemy- that was certainly true in this case...
Battle of Vrilya, Galactic Concordat- 18 August 2652
The Concordat Battlefleet departed the Vrilya system in late December 2651- by 27 February 2652, all fleets reported that they were in their IPs or 'initial positions', in this case somewhere in the outer reaches of each of the 13 Caleph systems that were to be attacked. And it was at this point that everything went to hell in handbasket.
As the orders were being issued to engage, blockade or invade the enemy it was immediately noticed that the Caleph defending ships in all the targeted systems were sallying out to the Fleet IPs... in other words, ALL the fleets were being engaged by the Caleph in the outer realms of 13 systems. Put another way, 14 separate attacks were being pre-emptively disrupted simultaneously. Most astonishingly, this was taking place without a declaration of war being issued. High Command's first impulse was to order all attacks that could to go forward; until it was reported that enemy fleet opposition was heavy and growing as ships were arriving in-system from elsewhere. This in turn gave rise to a sense of panic that far too many Concordat ships would be lost, and that realization was translated into an all-Fleet recall back to the Vrilya system. The Home-world, the Capital, one of the best-defended systems in the Concordat and the traditional home base for the Fleet.
Some fleets were able to extricate themselves from battle more easily than others: for example, the six troop transports of 5th Invasion Fleet were all destroyed, while 12th Fleet lost three of 18 ships whilst disengaging. All the same, High Command had begun to relax upon seeing that the situation had not devolved into a complete rout... UNTIL it was noticed that two large Caleph fleets were apparently following the Fleet back to- the Capital system. By this time the High Command had regained it's wits- yes a large (nearly a hundred ships) enemy force was approaching the Home-world, however- a Large Space Port , four Defense Bases and nearly three hundred ships would be defending Vrilya. In addition, all of the surviving troop transports were loaded with troops and also headed back to the Vrilya system, where they would be available to reinforce should there be completely unexpected ground assault on the Capital. Even so, there was a great deal of tension at the High Command on Vrilya...
In the end, while there were a couple of moments where things looked less than optimal, the Battle of Vrilya at least played out as hoped and expected. The fleets went into Patrol around Vrilya or the orbiting bases; the Caleph ships, attacking the Concordat ships, entered in close to the planet and the bases, rendering their ability to quickly escape null and void. It was a slaughter, with the vast majority of the Caleph ships destroyed, a few captured. The final tally: the Concordat lost 3x Capitals, 4x Cruisers, 4x Destroyers, 8x Frigates and 9x Troop Transports destroyed. Early on in this fiasco it was feared that losses would be far higher. The Caleph did manage to attack and take one medium-sized colony, and there were two other colonies that were battling revolts- in at least one case sparked by Caleph Espionage agent for certain.
At no time during these events was a Declaration of War issued by either side.
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The Battle of Vrilya described above was the largest battle I have ever played in DWU: a total of over 400 ships involved, checking on two revolts until I was satisfied that they would end well for me; controlling 300+ ships divided into 14 tactical fleets; jumping the troop transports (which die like dogs) out of harms way once it was apparent that there would be no ground assault on the Capital, etc. Coming as it as unexpectedly did on the heels of a phenomenon I had never before witnessed in-game, and over 300 years into the scenario, well... lets just say that this rated as the most fun I have ever had in a space-themed (possibly any-themed) game against AI. EVAR. And I still have the Caleph to deal with, and the Keskudon.