It's been a while since I read Conquerors, but I don't really remember it describing the Portuguese as incompetent, backwater or anything of the sort. And I would also be surprised if it labels them 'late to the gunpowder age'.

Let's first draw a picture of what state Portugal really was in at around the time. While it certainly wasn't a country of the most primary economic or political importance, labelling it backwater - implying some kind of isolation or separation from mainstream Europe - is just incorrect and unfair. From its inception as an independent kingdom in 12th century, Portugal cultivated links with the rest of Atlantic facing Europe. Its merchants could routinely be found in places like Flanders and England, and vice versa, merchants from abroad regularly visited and made permanent merchant communities in Portuguese towns like Lisbon and Porto. Furthermore, since the end of 13th century Italian merchants began regularly sailing to Flanders, a route which took them right next to pretty much entire coast of Portugal, where they frequently stopped. Now, not to make too outlandish claims, Portugal was still only a lesser stopover for Italians. And in the context of trade in the Atlantic, Portuguese exchanged their primary agricultural products of wine, olive oil and cork - which had to compete with those same products from Spain, France and others - for textiles and manufactured goods of Northern regions, which is usually considered as a sign of poorer manufacturing base and in general an economic handicap.
So to reiterate, Portugal had an existing, consistent and lucrative albeit not spectacular trade with Europe's biggest centres both in Northern and Mediterranean seas. They weren't the top players in it by any measure, but we certainly shouldn't look at their role condescendingly.

To proceed with the analysis. As far as the political and financial state of Portugal as a kingdom goes, the 14th century was dire. Series of wars with Castile, culminating in 1383-1385 war that brought Avis dynasty to the throne, left the kingdom quite impoverished and exhausted. The new king Joao I resorted to debasing to currency to pay the debts, an action of serious negative short term consequences for the individuals of the realm. Yet from the mess eventually came order. Joao's financial reforms in the long term paid off, just as he managed to consolidate the rule of the kingdom firmly in his and his family's hands. In international relations, Joao's marriage to Phillipa Lancaster strengthened Portuguese links with the English and the marriage of their daughter Isabella to Duke of Burgundy did the same to relations with Flanders.

With the above as a starting point, it was in the 15th century with the shift of focus on Africa that brought major benefits to Portugal. While their attempts to conquer Morocco were probably more a strain on financial resources and manpower than providing much tangible benefit, areas further south in the Atlantic were a much different story. Sugarcane - already grown in Algarve - was introduced to the island of Madeira with spectacular success and the exploration-raid-trade down African coast allowed Portugal to become rich by importing what was primarily African slaves, and to a lesser extent also ivory, malagueta pepper and gold dust. The last one enabled the Portuguese to even start minting their own gold coin - cruzado - a symbol of considerable financial stability.

As sailing South proved to provide much profit, the Portuguese were careful to keep developing naval capabilities to continue exploiting this large avenue of income, and were for a considerable time arguably the leaders of European navigational, cartographical, and astronomical science and were at the forefront in all things connected to general naval matters.

Gunpowder weaponry usage included. Whatever made you think Portuguese were late to the gunpowder age, it couldn't be further from the truth, and I can't stress that enough. Yes, a Portuguese fidalgo taking his sword and charging into a melee screaming 'Santiago' from the top of his lungs was a common sight well into the 16th and even 17th century. But that is in no way mutually exclusive with having and using considerable amounts of gunpowder weaponry and that's I think the most important lesson we can learn today and why I find Portuguese so interesting.

To give some examples. Already in 1415 one contemporary account of the taking of Ceuta mentions there was an early bombardment of the North African town which implies the usage of gunpowder artillery from ships. The account is vague and other accounts don't repeat this information, so I'll not press the case too much. But in 1437 we have several documents of Portuguese casually mentioning the usage of artillery, gunpowder and cannonballs (albeit most of them complaining of misusage and there not being enough of either) during the disastrous attempt to take Tangier. By 1450s when we have clear accounts that without any doubt mention Portuguese caravels going to Guinea having some form of artillery on board. Pastrana tapestries, showing Conquest of Arzila in 1470s show numerous gunpowder weapons in the Portuguese army, ranging from handheld handgonnes to wrought iron bombards of different sizes typical for 15th century, all the way to cast bronze cannons. In 1492-93 on his return from the first voyage to America Columbus - whose ship also had bombards - ran into a Portuguese ship and describes it as having the best artillery and arms he ever saw. From 1497 onwards the numerous text documents, as well as archaeological finds, clearly show Portuguese had considerable number and variety of artillery on their India going vessels. Later, in 1525, a list of ordnance in Indian Ocean lists almost a thousand different pieces scattered throughout their forts and ships, of which over two-thirds were bronze, and the rest of wrought iron - inferior yet still useful. At the same time contemporary records show Portuguese forts in Morocco had at least another two thousand of similar cannon pieces, and as the records are incomplete estimates go to over 3000 pieces all together only in Morocco, and who knows how many more in Portugal proper. This large number of artillery - most of which were smaller swivel pieces typical for the Portuguese - was unrealistic for Portuguese to make themselves. Although they indeed had their own cannon foundries, they could never reach this huge capacity that was needed. Which is why Portuguese imported many of their artillery from abroad, mainly Flanders (which in at least 15th and 16th century was one of the main ordnance production centres) and others like Spain and Italy etc.

Bigger problem existed with getting capable experience gunners. Their number in Portugal was just too few and as late as 1590s you would easily find foreigners hired as master gunners on Portuguese ships. It is possible to conclude from looking at this data that Portuguese didn't have their own gunpowder artillery or gunners at all, but really the issue is that the needs far outstripped the locally available supply.

To round up everything already said with an analysis of military situation both in Portugal and the Indian Ocean. I've already mentioned continuous military involvement in Morocco where Portuguese had for some time been taking and then holding strategic towns and coastal fortresses - exactly the type of warfare they would face in the Indian Ocean. I should also add that Portugal was also involved in 1470s in another war against Castile and then in 1480s some Portuguese fidalgos joined Castilians in the conquest of Granada. My overall point is, by 1500 Portuguese had considerable relevant military experience.

In the coastal regions of Indian Ocean at least the fifty years preceding the Portuguese arrival were relatively peaceful. The old powers, like Mamluk Egypt, Deccan sultanate, Vijayanagara empire were busy declining and disintegrating and anyway showed little interest in naval matters. The future superpowers Ottomans, Safavids and Mughals would reach the coasts of Indian Ocean only after Portuguese already had entrenched themselves. In the vacuum, plenty of relatively smaller states existed on the coasts, supporting themselves by taxing seaborne trade. Yet none had a 'deep sea' navy and few if any participated in conquest overseas or long range military expeditions, other than maybe with their immediate neighbours. They did usually have large naval fleets in the form of huge number of smaller oared vessels that could swarm enemy ships, a tactic which had great success against conventional vessels, but which had plenty of drawbacks when faced against ships packed with artillery like the Portuguese brought, which blew these smaller boats from the water, quite literally.

So there you have it. Portuguese could arm themselves drawing from their own resources, and not less importantly also from the resources of the rest of Europe with which they were quite connected. And this they could easily pay for with profits first from the exploitation of Africa and then Indian ocean area itself. Navies in the Indian Ocean weren't prepared for such weapons and tactics, especially as Portuguese moved in fast. Once the seas were dominated, Portuguese then engaged into the types of amphibious assaults, sieges and counter sieges of which they had plenty of experience from Morocco. Once they took key positions and dug in, supported by their artillery they were next to impossible to dislodge. It's also important to note that the Portuguese weren't always successful. Their attempts were just as often rebuffed as they were victorious, and many their victories often came by exploiting defenders disunity or preoccupation with other events or other lapses in defences.

So there it is. A short overview of where Portugal was and what it faced in their arrival to the Indian Ocean. Hope it clears up the overall image.