I start by moving my units towards the west where Isengard will without doubt soon invade you. Giving you more tradeable goods as well as a faster way between your cities. In Entwade and Woldberg I begin the construction of roads.
They are quite powerful if you wield them correctly. In Edoras and Hornburg I construct a barracks because you can`t have your armies consisting only of cavalry. The third option, which is also my favorite, is to mix option one and two. That is why you must always have an army ready to face the enemy. The second option is to make your kingdom insanely rich, thus enabling you to defeat the mighties of enemies, but beware! If you only construct economical buildings your plan might backfire because Isengard will take advantage of your lack of military. The first option is to go all in for recruiting units, making your kingdom a military powerhouse, though remember that it can cause your economy to be crippled. At turn one you must choose one of three ways for Rohan. It can work to blitz Isengard in the beginning of your campaign, but remember that you must NOT only have your armies consist of cavalry only. This very reason is caused by too much focus on war and creating huge armies. If you have ever played Rohan, you must know that you will sometimes have your economy drop drastically. They are the generals you will be using most of the time because of their ability to win nearly all battles. You start with several generals, including both King Thengel and Lord Theoden. It is a mighty realm with several strong cities, the most powerful of them all Helms Deep and Edoras. What you see infront of you now, is your kingdom.