I don't know ho manufactured it, but the serial number would appear to indicate a 1989 model. The format was common among Taiwanese manufacturers. There appears to be a Country of Origin label on the front of the lower head lug, though I can't read it from the photo. The graphics are reminiscent of the Centurion models from this period , while the model name is one used by Fiori. However, I don't think there is any connection and it's simply a case of appropriating attractive graphics and an intertesting model name.
Royce Union is a very old brand that originated in 1904. Over the years, the bicycles have been manufactured in various countries including the Netherlands, Germany, Italy, Japan and Taiwan. I suspect the brand has changed ownership several times over the years. Since at least the early 1960s it appears to have been owned by marketing firms who have had the bicycles contract manufactured to a price point. As such, they are likely the contract manufacturer's standard frame design, with options from their standard component packages and colour range. About the only thing specific to the brand would be the decals and head badge.
It's definitely bottom of the barrel for the era, with a hi-tensile frameset, steel rims, nutted rear axle, steel chairings swaged to aluminum crankarms, stem mounted shift levers and brake safety levers. Royce Union typically didn't stray from the entry level market.