Roberts' linear tactics concept had an early critic in the younger historian Geoffrey Parker, who asked why the supposedly outdated Spanish tercios defeated the Swedish linear formations at the battle of Nördlingen in 1634. Parker instead suggested that the key development was the appearance of the trace italienne fortifications in early modern Europe. In this view, the difficulty of taking such fortifications resulted in a profound change in military strategy. "Wars became a series of protracted sieges", Parker suggests, and open-pitch battles became "irrelevant" in regions where the trace italienne existed. Ultimately, Parker argues, "military geography", in other words the existence or absence of the trace italienne in a given area, shaped military strategy in the early modern period, and lead to the creation of larger armies necessary to besiege the new fortresses and to garrison them. In this way, Parker placed the birth of the Military Revolution in the early 16th century. He also gives it a new significance, not only was a factor in the growth of the State, it was also the main factor, together with the "Naval Revolution" to the rise of the West over other Civilizations.