Imperium is the official font of the Imperium Romanum, the Roman Empire.
Only since my youngest son decided to learn Latin do I know that the Romans had another font for everyday use, Scriptura Vulgaris an italic script.
Among typomaniacs the official Capitalis Monumentalis from the Trajan column (113 AD) is considered the ultimate in Roman lettering. Based on this lettering a variety of font designs are available, but all of them have tried to better the Roman original. Albrecht Dürer was one of the first ones (1525) to reconstruct the roman capitals, Frederic Goudy did a fantasic job as well as lots of others (most of the fonts are called Trajan).
I thought I would just give you the unchanged original as it appears on the Trajan column without constructing or putting a philosophy behind the letters.
Unfortunately, because of stupid graffiti tourists, the modern Romans had to surround the column with heavy duty iron bars. I could not trace the lettering directly, so I had to rely on my photographs. In order to make it usable for today, I added small caps, numerals and all the diacritical marks — even Yen and Euro signs. I designed a complete set without changing the original appearance.
The Romans were heavy users of ligatures so I added all the ligatures I could find (capitals only). To top things off, I added a relief capital letters alphabet for use as initials. It has got the same spacing as the smallcaps alphabet, so you can produce a two-tone effect by overlaying the relief over the normal capitals.
Your very imperial Gert Wiescher