Unit 1 covers roughly 1450 to 1648, and four changes run through it at once. The CED states them as the unit's key concepts, and almost every question draws on at least two:

• The rediscovery of classical works 古典著作 from ancient Greece and Rome, and observation of the natural world, changed how many Europeans saw their world.
• Europeans explored and settled overseas territories, encountering and interacting with Indigenous populations 原住民.
• European society and everyday life were increasingly shaped by commercial and agricultural capitalism 商业与农业资本主义, though older traditions persisted alongside it.
• The struggle for sovereignty 主权 within and among states produced varying degrees of political centralisation.

That last phrase - varying degrees - is a standing instruction for the whole course. European History rewards answers that say how far a change went in one place compared with another.

Italian Renaissance humanists 人文主义者, including Petrarch 彼特拉克, promoted a revival of classical literature and created new philological 语文学 approaches to ancient texts - reading them critically, in their original languages, as historical documents.

That revival had three effects the CED names separately:

• Spread by the printing press 印刷机, the humanist recovery of Greek and Roman texts challenged the institutional power of universities and the Catholic Church.
• Admiration for Greek and Roman political institutions supported a revival of civic humanism 公民人文主义 in the Italian city-states, producing new works of political thought.
• Rulers and popes concerned with enhancing their prestige 提升声望 commissioned paintings and architecture on classical models.

The third point is the one students underuse. Renaissance art is examinable as political evidence: patronage was a claim to legitimacy, not only a taste in pictures.

As Renaissance ideas moved north, they changed. The Northern Renaissance retained a more religious focus, producing a human-centred naturalism 以人为中心的自然主义 that considered individuals and everyday life as proper subjects for art.

Intellectually, the key development is Christian humanism 基督教人文主义, embodied in the writings of Erasmus 伊拉斯谟, which put Renaissance learning at the service of religious reform 宗教改革. Holding that link makes Unit 2 far easier: the Reformation did not arrive from nowhere.

The CED gives printing a topic of its own for a reason: the invention of printing promoted the dissemination of new ideas.

Printing is best understood as an amplifier rather than a cause. It did not create humanism, religious dissent, or political argument - but it changed their speed, reach, and cost, which is what allowed ideas to escape the control of the institutions that had previously governed which texts circulated.

The new monarchies 新君主国 laid the foundation for the centralised modern state by:

• establishing monopolies on tax collection 征税垄断权;
• employing military force 军事力量 under royal control;
• and taking increasing control of law and administration.

Two counterweights are also examinable. Commercial and professional groups gained power across Europe and played a greater role in political affairs. And continued political fragmentation in Renaissance Italy provided the background for new concepts of the secular state 世俗国家 - the theory came from the place where centralisation had failed, not succeeded.

Some monarchs, including Henry VIII and Elizabeth I, also initiated religious reform from the top down to strengthen royal control - a point that belongs to both this unit and the next.

Advances in navigation, cartography, and military technology enabled Europeans to establish overseas colonies and empires. Technology is the enabling condition; the CED then gives the motives separately:

• European states sought direct access to gold, spices, and luxury goods to enhance personal wealth and state power.
• The rise of mercantilism 重商主义 gave the state a new role in promoting commercial development and acquiring colonies.
• Christianity was a stimulus 宗教动因 for exploration, as governments and religious authorities sought to spread the faith - and for some it also served as a justification.

Keep enabling conditions and motives in separate categories. A question asking "why" wants motives; a question asking "how it became possible" wants the technology.

Europeans established overseas empires and trade networks through coercion and negotiation 强制与谈判 - both, not one. Where local states were strong, Europeans negotiated for trading rights; where they were not, coercion followed.

Competition among European states for these networks reshaped relations at home. Commercial rivalry became a standing cause of European war, which is a continuity that runs all the way to Unit 7.

The Portuguese established a commercial network along the African coast and in South and East Asia in the late fifteenth and sixteenth centuries; other states followed.

The Columbian Exchange 哥伦布大交换 - the exchange of new plants, animals, and diseases - is presented by the CED with deliberate double vision, and both halves are examinable:

• It created economic opportunities for Europeans.
• It facilitated European subjugation and the destruction of Indigenous societies, chiefly through disease.

Economically, the exchange of goods shifted the centre of economic power in Europe from the Mediterranean to the Atlantic states. That shift explains why the leading powers of Unit 3 are not the leading powers of Unit 1.

Europeans expanded the trade of enslaved Africans in response to the establishment of a plantation economy 种植园经济 in the Americas and to demographic collapse among Indigenous populations.

The causal chain is explicit in the CED and should be reproduced as a chain: plantation agriculture demanded labour on a scale the Americas' devastated population could not supply, and that demand was met by an expanded Atlantic trade in enslaved people.

The Renaissance and the voyages are the visible half of this unit; the CED also asks for the economic base underneath them, because it is what the later units change.

Subsistence agriculture 自给农业 was the rule almost everywhere: a family grew what it ate, with little surplus to sell. Land was worked in open fields and rotated to keep it fertile — a three-crop rotation 三圃轮作 in the north, where wetter summers allowed a spring sowing as well as an autumn one, and a two-crop rotation 二圃轮作 around the Mediterranean, where the dry summer forced half the land to lie fallow each year. Most peasants did not own the land; they paid rent to a landholder, in produce, in money, or in labour service.

That base explains the fragility of the period: a single failed harvest meant famine, because there was almost no stored surplus and little trade in grain over long distances.

Towns grew faster than they could cope. Urban populations rose through the sixteenth century, and sanitation 卫生 did not keep pace: waste ran in the streets, water was drawn from contaminated wells, and overpopulation 人口过剩 in the poorer quarters made epidemic disease spread quickly. Plague outbreaks stayed a recurring feature of European life for this whole period.

States acted on religion and morality, not only on taxes. Governments and city councils regulated public behaviour: attendance at worship, permitted forms of belief, marriage, drinking, gambling and morality 道德 offences generally. This is worth remembering because it is the same instrument the confessional states of the next unit use on a larger scale — the machinery existed before the Reformation gave it a new purpose.

Innovations in banking and finance promoted the growth of urban financial centres and a money economy 货币经济. Economic change produced new social patterns, while traditions of hierarchy and status continued - the two coexisted, which is the CED's own framing.

Most Europeans still derived their livelihood from agriculture and organised life around the seasons, the village, or the manor. Within that, a sharp divergence opened:

• Western Europe moved toward a free peasantry 自由农民 and commercial agriculture.
• In the east, serfdom was codified 农奴制被法典化 as nobles continued to dominate the rural economy.

The same commercial pressure produced opposite outcomes, and that is exactly why it is examinable. Two related consequences: landlords attempting to increase revenues by restricting traditional peasant rights provoked revolt 反抗; and migrants to the cities strained resources and challenged the ability of merchant elites and craft guilds to govern.

Finally, from the late sixteenth century Europeans responded to economic and environmental pressure - including the Little Ice Age 小冰期 - by delaying marriage and childbearing, a demographic adaptation worth knowing because it is unusual evidence.

The unit's reasoning skill is causation.

Worked example (a real AP exam question). AP European History short-answer questions in this unit ask, for example, to "Explain one way in which the development of printing affected European intellectual life in the period 1450 to 1648." A full-mark answer gives the mechanism, not the fact: "Printing allowed humanist editions of Greek and Roman texts to be reproduced cheaply and identically, so scholars across Europe could read and compare the same critical editions. This weakened the control that universities and the Church had exercised over which texts circulated, and made it far harder to suppress an argument once it was in print." Notice the shape: affected requires a consequence traced through a process.

• "Varying degrees" is the CED's own phrase for centralisation. Compare how far, not merely whether.
• Renaissance art is political evidence. Patronage was a claim to prestige and legitimacy.
• Treat printing as an amplifier, not a first cause. That framing answers most printing questions.
• Separate technological enablers from motives for exploration. Questions ask for one or the other.
• The Columbian Exchange has two sides - European opportunity and Indigenous destruction. Give both.
• The east-west divergence in serfdom is high-value and frequently missed. One cause, two opposite outcomes.