"The plaza of this small site is majestic, presenting the visitor with an expanse of level courtyard that the towering stelae--the tallest soars to nearly 35 feet--separated into areas of enclosure and sweeping processional spaces. Given Quirigua's modest size and population, one might wonder what ritual spectators and participants visited the site to take part in Cauac Sky's period-ending rites. Who gathered at Quirigua to observe these celebrations? In the aftermath of a war that had separated the site from Copan and its hinterlands, what allies of Cauac Sky might have assembled to honor his claims to sovereign kingship?
It is interesting to consider Quirigua's relation with a network of large, apparently powerful non-Maya sites located to its east, in the lower drainage of the Motagua Valley. The rise of the Lower Motagua Valley (LMV) centers appears to correspond closely to the Late Classic florescence of Quirigua, and they appear to have figured importantly in its commercial sphere...Edward Schortman and Seiichi Nakamura (1991) believe that the LMV sites operated in a commercial domain that rivaled Copan's La Venta Valley/Naca Valley trading network.
[The LMV sites] appear to have co-existed in such a close association with Quirigua that numerous authors have pointed out the apparent coincidence between Cauac Sky's victory [over 18-Rabbit of Copan] in 738 and their rise to power. Sanders has made the very interesting suggestion that Quirigua's victory in its war with Copan may have been accomplished with the alliance of its Lower Motagua Valley neighbors. If correct, this scenario might explain the viewership of the rites that Cauac Sky planned for the Great Plaza of his site; it may also provide a glimpse into his motivations for appropriating a strategy that his adversary had deployed so brilliantly in his own patronage of monumental art."
Elizabeth A. Newsome, Trees of Paradise and Pillars of the World: The Serial Stela Cycle of 18-Rabbit-God K, King of Copan, p. 64