Only forty of Poyarkov’s men are left alive by the spring of 1644.

Joined now by the overwintering party, they push down the Zeya to the Amur.

They have to fight their way down the Amur through numerous ambushes, their reputation having preceded them.

They reach the Gilyak country at the mouth of the Amur by autumn.

Poyarkov, with so many enemies behind him, thinks it unwise to return by the same route.

They build boats this winter.

The Ainu people are the earliest inhabitants of the Kuril Islands, although there are few records that pre-date the seventeenth century.

The Japanese administration had first taken nominal control of the islands during the Edo period, in the form of claims by the Matsumae clan.

On "Shōhō Onkuko Ezu", a map of Japan made by the Tokugawa shogunate, in 1644, there are thirrty-nine large and small islands shown northeast of the Shiretoko peninsula and Cape Nosappu.

The religious life of the Jewish community in K'ai-feng has been permanently disrupted by the protracted period of war and social upheaval that has accompanied the establishment of the Ch'ing, or Qing (Manchu) dynasty in 1644.

Jewish religious education is also severely disrupted at this time, and these factors, combined with the increased tendency of K'ai-feng Jews to intermarry with Han Chinese or convert to other religions, result in a rapid decline in religious fervor, although the synagogue will be rebuilt in 1653.

The colonists on Mauritius are in 1644 faced with many months of hardships, due to delayed shipment of supplies, bad harvests and cyclones.

The colonists during these months can only rely on themselves by fishing and hunting.

Torricelli famously writes in a letter of 1644: "We live submerged at the bottom of an ocean of air."

Torricelli gives the first scientific description of the cause of wind: “... winds are produced by differences of air temperature, and hence density, between two regions of the earth.”

Descartes, in 1644, advances the notion that the activities of organisms (including humans) occur as a reaction to external stimuli.

The World, originally titled Le Monde and also called Treatise on the Light, written by Descartes between 1629 and 1633, contains a relatively complete version of his philosophy, from method, to metaphysics, to physics and biology.

A follower of the mechanical philosophy, a form of natural philosophy popular in the seventeenth century, Descartes thinks everything physical in the universe to be made of tiny "corpuscles" of matter.

Corpuscularianism is a viewpoint closely related to atomism.

The main difference is that Descartes maintains that there can be no vacuum, and all matter is constantly swirling to prevent a void as corpuscles move through other matter.

The World presents a corpuscularian cosmology in which swirling vortices explain, among other phenomena, the creation of our solar system and the circular motion of planets around the Sun.

Because the work endorses the Copernican view of the moving earth, Descartes had cautiously delayed its release when he heard of the condemnation of Galileo’s Copernicanism by the Catholic Church in Rome and the subsequent burning of the related works.

Descartes had discussed his work on the book, and his decision not to release it, in correspondence with another philosopher, Marin Mersenne.

Some material from The World is revised for publication as Principia philosophiae or Principles of Philosophy (1644), a Latin textbook at first intended by Descartes to replace the Aristotelian textbooks used in universities.

In the Principles, the Copernican tone is softened slightly with a relativist frame of reference.

Moses Amyraut, also known as Amyraldus, pastor of the French Protestant theologian church and professor of theology at the University of Saumur from 1633, had soon thereafter published his Traité de la predestination, in which he tried to mitigate the harsh features of predestination by his Universalismus hypotheticus.

God, he teaches, predestines all men to happiness on condition of their having faith.

This modifications to Calvinist theology regarding the nature of Christ's atonement has come to be called Amyraldism or Amyraldianism.

Simply stated, Amyraldism holds that God has provided Christ's atonement for all alike, but seeing that none would believe on their own, he then elected those whom he will bring to faith in Christ, thereby preserving the Calvinist doctrine of unconditional election.

While this view maintains the particularity of sovereign grace in the application of the atonement, the belief that Christ paid for all the sins of all people even though not all are saved either requires double payment for sin, or one of the premises is wrong.

Charged with heresy, Amyraut had been acquitted at the national synod held at Alençon in 1637.

The charge is brought up again in 1644 at the national synod of Charenton, when he is again acquitted.

The Confederates send around fifteen hundred men under Alasdair MacColla to Scotland in 1644 to support the royalists there under James Graham, 1st Marquess of Montrose, against the Covenanters, sparking a Civil War—their only intervention on the Royalist side in the civil wars in Britain.

Jeanne Mance, a French settler of New France who is one of the founders of Montrèal, in 1644 founds the Hôtel-Dieu de Montrèal, the first hospital in North America north of Mexico.

Supported by Anne of Austria, wife of King Louis XIII, and by the Jesuits, Mance is a member of the Society of Our Lady of Montreal, whose aim is to found a hospital in Montreal similar to the one in Quebec.