The United States gains Guam as one of the spoils of its 1898 war with Spain.

Carsten Borchgrevink, commanding the 1898—1900 British Southern Cross expedition, goes ashore at Cape Adare in February 1899 and, with nine men, is the first to pass a winter and following summer in Antarctica.

New Zealand contributes troops to Britain’s war with the Boers.

The fighting between U.S. and Filipino forces that breaks out in February 1899 results in the Philippine-American War and a subsequent series of independence movements (or guerrilla uprisings, depending where one’s sympathies lie).

Russia, in threatening China, gains concessions from Europe’s Great Powers.

August Strindberg expresses naturalism in his seminal plays.

Some critics think that the Swedish dramatist suffered from severe paranoia in the mid-1890s, and perhaps that he temporarily experienced insanity.

Others, including Evert Sprinchorn and Olof Lagercrantz, believed that he intentionally turned himself into his own guinea pig by doing psychological and drug-induced self-experimentation.

He writes on subjects such as botany, chemistry, and optics before returning to literature with the publication of Inferno (1897), a (half fictionalized) account of his "wilderness years" in Austria and Paris, then a collection of short stories, Legends, and a semi-dramatic novella, Jacob Wrestling (both printed in the same book 1898).

Both volumes have aroused curiosity and controversy, not least due to the religious element; earlier, Strindberg had been known to be indifferent or hostile to religion and especially priests, but now he has undergone some sort of conversion to a personal faith.

In a postscript, he notez the impact of Emanuel Swedenborg on his current work.

"The Powers" are central to Strindberg's later work.

He says that "the Powers" are an outside force that has caused him his physical and mental suffering because they are acting in retribution to humankind for their wrongdoings.

As William Blake, Ralph Waldo Emerson, Honoré de Balzac, and William Butler Yeats had been, he is drawn to Emmanuel Swedenborg's mystical visions, with their depictions of spiritual landscape and Christian morality.

Strindberg will believe for the rest of his life that the relationship between the transcendental and the real world is described by a series of "correspondences" and that everyday events are really messages from above, of which only the enlightened can make sense.

He also feels that he has been chosen by Providence to atone for the moral decay of others and that his tribulations are payback for misdeeds earlier in his life.

Strindberg had spent the tail end of 1896 and most of 1897 in the university town of Lund in southern Sweden, a sojourn during which he made a number of new friendships, felt his mental stability and health improving and also firmly returned to literary writing; Inferno, Legends and Jacob Wrestling were written there.

In 1899, he returns permanently to Stockholm, following a successful production there of Master Olof in 1897 (which is re-staged in 1899 to mark Strindberg's fiftieth birthday).

He has the desire to become recognized as a leading figure in Swedish literature, and to put earlier controversies behind him, and feels that historical dramas are the way to attain this status.

Though Strindberg claims that he is writing "realistically," he freely alters past events and biographical information, and telescopes chronology (as often done in most historical fiction): more importantly, he feels a flow of resurgent inspiration, writing almost twenty new plays (many in a historical setting) between 1898 and 1902.

His new works included the so-called Vasa Trilogy: The Saga of the Folkungs (1899), Gustavus Vasa (1899), and Erik XIV (1899).

Gustav Klimt's style has grown increasingly experimental.

Critics had roundly attacked his murals for Vienna University, commissioned by the State in 1894, for their fantastical imagery and their bold, decorative style.

Soon after he paints three allegorical murals for the ceiling of the University of Vienna auditorium that are violently criticized; the erotic symbolism and pessimism of these works create such a scandal that the murals are rejected.

Sigmund Freud divides the mind among the id, ego and superego and expounds psychoanalytic theory in “The Interpretation of Dreams,” in which, following a critical review of existing theory, he gives detailed interpretations of his own and his patients' dreams in terms of wish-fulfillments made subject to the repression and censorship of the "dream-work".

He then sets out the theoretical model of mental structure (the unconscious, pre-conscious and conscious) on which this account is based.