What-ifs in history are always difficult to answer accurately, simply because we really never know what would have happened. Nonetheless, I will offer an opinion based upon my understanding of the period.

To your first questions: we must first establish the baseline that the Jacobite army was not only made up of Highlanders. While the initial landing and call-to-arms were indeed made in the Western Highlands of Scotland, and though Gaels made up the front-line shock-troops of the Jacobite army, by the rising's end more Lowlanders and North-Easterners had constituted the bulk of the total Jacobite martial constituency.

Now we may turn to London, which was frantically preparing to defend itself as the Jacobite forces drew closer in the winter of 1745-6. The panic from Charles Edward Stuart's successes and rapid advance into England set the stock market into a tumble and the British army had been calling up troops from the Continent and fortifying the city gates with artillery brought from anywhere it could requisition them. And critically, a significant mob was starting to coalesce to engage with the threat should the Jacobites enter the capital.

But the thing to focus on is not the resistance that could be brought to bear on the approaching revolutionary army, but how the Jacobites would have been able to hold London, effect a smooth transition of power, and maintain a defensible stronghold with open streams of supply from both Scotland and France. Holding Edinburgh for a short time without taking the castle did not ensure that Charles Edward was the master of Scotland, and it is important to note that Jacobite martial support – especially outwith 'North Britain' – was inadequate and difficult to hold together. Capturing London, therefore, does not directly translate to being able to capture the hearts and minds of enough of the British populace to sustain a martial victory – as was the case with Edinburgh soon after the army left.

This same premise may be layered upon a Jacobite victory at Culloden, though it likely would have been a major blow to British confidence in the government's ability to simultaneously wage a sustained war on two fronts: on the Continent and in its own backyard. Most scholars agree that by 1745 the popularity of Jacobitism was not wide enough and its ideologies neither accessible nor effective enough to keep the movement going far beyond a victory at Culloden. It likely could have extended the rising by months, but the odds were always very much against Charles Edward and the Jacobite 'cause' for many reasons, including those mentioned above: numbers, supply, effectiveness, and support. Could France have then poured resources into the campaign or might thousands more have rallied to the Jacobite standard? Possibly, but the momentum by that late point in the century-long life of Jacobitism was clearly on the side of progressive, mercantile-focused Hanoverian British and the relative comfort that had finally settled over the fledgling empire due in part to the Union of 1707. This will always be debatable, especially in Scotland. But only 1.14% of Scotland's population took up arms for the Stuarts, and that shows us something. The rates of those from Ireland and England are infinitesimally smaller.

This takes us cleanly into your final question: what inspired people to fight for the Jacobites? The answer largely depends on what part of the British population you are considering. Like any civil war, the Jacobite rising was set against an intensely complex backdrop, and people tend to participate or abstain from participating in such conflicts due to a variety of factors. I explore this topic in my doctoral thesis, 'Spines of the Thistle: The Popular Constituency of the Jacobite Rising in 1745-6', which specifically deals with the plebeian participants, and includes themes of recruitment, motivation, and demographics. The thesis is available as a free download in the University of St Andrews digital repository. The section most relevant to your question is pp. 34-79.

As a kind of coda, it is worth noting that any mention of 'benefits' to those involved with a Jacobite victory must be qualified. Would a transfer of power to the Stuarts have been more beneficial for some? Again, possibly, but we cannot reliably forecast what changes would have been implemented. Britain was rapidly growing in economic and military power and Scotland – especially the Highlands – was already in a state of major transformation. The Stuarts were conservative, divine right monarchs who were more interested in ruling over a regnally-united Britain than an independent Scotland alone, and this was proven by Charles Edward's insistence on crossing the border into England. The Presbyterian Church was closely aligned with the Hanoverian government and only a minority of Scots were Catholic (more, including most Jacobites, were Episcopalians), so it would not have been easy to shift the church structure without further massive upheaval. The clan system was already well beyond its sell-by date and though the depredations undertaken in the Highlands by British troops after Culloden were horrific and unconscionable, the clan chiefs themselves had for many years been hastening structural changes that traded traditional, community-based ideals for capitalistic leverage. Who that really benefitted is equally as questionable.

With regard to further reliable reading on the history of Jacobitism, I have recently written up a list of 'essentials' on my research blog, Little Rebellions. Hoping that this helps a bit and answers your questions. If not, please feel free to follow up with me.

With best wishes,

Dr Darren S. Layne
Creator and Curator, The Jacobite Database of 1745
(formerly of the Institute for Scottish Historical Research, University of St Andrews)