It’s not often that you get a question asking for what is essentially a narrative response, and over such a broad-ranging period to boot. As such I must apologise for placing greater emphasis on certain areas than others. Additionally, as this answer was originally intended to be based around an older version of the question from a few days ago in which the main title wasn't just referring to the 'early' part, it goes on much longer than that.

Looking into the plot summary of Apostle, it seems that the flashback sequences that occur take place in 1900, at the height of the Boxer Rebellion. However, consistent, direct commercial and religious contact with the West was far older than that. The trouble is that you’ve asked a somewhat broad-ranging question, as there’s an explicit question as to how Chinese people reacted to proselytisation and colonialism at first, which takes us back to the 16th century when persistent contact between the two was firmly established, another for a timeline of European contact, where the high point is really the 18th and 19th centuries, and you implicitly want to know about the Boxers, which is all the way forward in 1900. Not that I’m complaining, of course. Just that there’s a whole lot of stuff to get through. So strap in!

Part I: The Pre-‘Humiliation’ Era - Early Interactions, 1500-1793

The 1500s, in my view, should be marked as the real beginning of persistent Sino-Western interaction both from religious and imperialistic angles, but with very limited impact. I would consider the 1550s as the real watershed mark, although there had been trade relations for decades prior. Portugal, after several years occupying islands in the Pearl River Delta for use as trading bases, negotiated a settlement with Ming Dynasty authorities in Guangdong Province in 1557, whereby the Portuguese would be permitted to rent land on the Macau Peninsula with which to establish a permanent settlement for trade purposes. Meanwhile, 1556 saw the first successful entry into China by a Catholic missionary, Gaspar da Cruz. However, influence was generally quite limited at this stage. Portugal would not even technically own the land on which Macau was built until 1887 (albeit having stopped paying rent since 1849), and missionaries generally found it quite hard to actually convert anyone. It has been argued that the problem was due to a lack of appreciation for the different tastes of the elite and the masses when it came to religion: the Jesuits decided to target the elite with a decidedly spiritual bent, which was widely rejected due to the elite having more practical designs and an interest in the social, rather than personal implications of their religious doctrines. One Confucian official even rebuked a Jesuit missionary as simply peddling Buddhism under a different name. (This association reached somewhat comical extremes in the 1850s, when a loyalist report on the Taiping, the Zeiqing Huizuan, alleged that their early form, the Bai Shangdi Hui (God-Worshipping Society), was a branch of a south Chinese secret society known variously as the Tiandihui (Heaven and Earth Society), the Tiandihui (Increasing Brothers Society), and all were ultimately part of the Catholic Church.)^1 ^a

From then on there continued to be plenty of European visitors to China, both missionaries and merchants, but the extent of the interaction would deepen throughout the 1600s. The former might find themselves part of the imperial court, most famously the case for Matteo Ricci, who in 1601 became the first European admitted to the Forbidden City, where his scientific knowledge was put to use to assist the Ming emperors. Although there were a few issues, this survived the upheavals of the Qing conquest (traditionally dated to 1644 onwards) and persisted well into the next dynasty, with the Qianlong Emperor (r. 1736-1796/9) in particular maintaining a substantial entourage of Jesuit scholars, the last of whom died in 1813 (theoretically this was a lifelong appointment with no chance of return.)^2 On the mercantile front, Portugal was not alone in trading with China. Spain and the Netherlands were also active here, and traded with the Ming from their colonies in Southeast Asia and, later on, Taiwan (then not part of Chinese territory; the Spanish colony in the north around modern-day Taipei and Keelung was founded in 1626, the Dutch around Tainan and Kaohsiung in 1624, the former being annexed by the latter in 1642 as part of the Eighty Years’ War.) Spanish silver from South America trickled in, and by the early 1700s had almost certainly supplanted Japan as China’s main external silver source.^3 Recreational opium smoking in the form of madak, tobacco prepared by soaking in opium syrup, was introduced to the coastal provinces of Fujian and Zhejiang, likely by the Dutch, at least by the early Qing period.^4 ^5 But relations were not wholly positive between China and the Western powers. John Weddell, a British East India Company captain, forced the authorities in Guangdong open trade at gunpoint in 1637.^2 Zheng Zhilong, a Fujianese pirate who had worked for the Dutch East India Company (VOC), became a prominent Ming coastal official and had to fight off a fleet assembled by his former employers to deal with him in 1633, whilst his son, Koxinga, would go one step further in sailing to Dutch Taiwan and expelling them from their southern colonies of Saccam and Zeelandia in 1661-2 in order to secure a base from which to hold out against the rising Qing.^6 Tensions also escalated on the frontier with Russia, as expansion into Siberia towards the Amur River came up against the heartland of China’s new Manchu rulers. Qing and Korean troops fought Cossacks on the Amur between 1654 and 1658, and a campaign to seize Cossack fort at Albazin from 1687-89 culminated in a Qing victory and the signing of the Treaty of Nerchinsk, which asserted Qing control over the north bank of the Amur.^7 1686 saw the establishment of a customs office at Canton, heralding the beginning of a more restrictive phase in Sino-Western relations.

Whilst it would be simply factually wrong to characterise the 18th century as a complete reversion to isolationism, the openness of earlier years did contract somewhat. Whilst Jesuit and Orthodox missions in Beijing would remain, following a Papal bull of 1715 condemning Chinese religious practices, the Kangxi Emperor (r. 1661-1772) had all Jesuit missionaries without significant technical skills expelled,^8 and furthermore proselytisation, which was generally frowned upon before, was also increasingly opposed, though largely nonviolently. Although trade with various powers was growing, there was an increasing move towards a more strongly regulated set of trade relations, with Canton and its Thirteen Factories (a large block of office and warehouse buildings to which the Westerners were confined during the trading season) as the focal point. 1757 saw the restriction of trade by all Western nations save for Spain to Canton (Spain was still permitted to trade at Amoy (a.k.a. Xiamen)), where the Qianlong Emperor had begun implementing new measures to regulate trade, culminating in the establishment of a merchant monopoly, the Cohong (corruption of Cantonese Gung Hong), in 1760, and an attempt by British trader James Flint to petition for a loosening of the restrictions led to his imprisonment and exile. Under the Canton System, whilst European trade remained immensely lucrative (tariffs on tea at some points contributed as much as 10% of British government revenues (excluding India)), and indeed the merchants, especially of the East India Company with its monopoly on Anglo-Chinese trade, were satisfied, private merchants, particularly in Britain but also in America, began clamouring for more open trade relations. In this they were supported by their respective states, who saw substantial economic opportunities in more active, unrestricted commerce with China. In addition, Protestant missionaries also began to follow in the footsteps of the Jesuits and sought to expand their activities. On the Chinese side, however, the status quo was generally satisfactory. Western goods remained incredibly popular among the wealthy elite, and there was minimal missionary activity that would be concerning. Whilst the 1793-4 Macartney Embassy ultimately failed spectacularly, it failed to significantly alter the nature of Sino-Western relations, and the Qianlong Emperor refused to allow his private anger at British presumptuousness to lead to worse diplomatic incident.^2 All in all, relations seemed stable, and there was little to suggest that there would be the sort of imperialistic activity or the anti-missionary violence that you would have seen during the Boxer Rebellion of 1900 as depicted in Apostle.