Question: What was the nationality of the person who wrote Variations on a Theme by Tchaikovsky?

Context articles: Venezuelan nationality law
Variations in F minor
Variations on a Rococo Theme
Brazilian nationality law
Anton Arensky
Multiple citizenship
Variations on a Theme by Tchaikovsky (Arensky)
Variations on a Theme by Haydn
Nationality
Cornelius Lyons

Venezuelan nationality law is based on the principle of Jus soli.
 Any person born in Venezuela acquires Venezuelan citizenship at birth, irrespective of nationality or status of parents.
 Nationality law is regulated by Section 1 of Chapter 2 of the Constitution of Venezuela and by the Nationality and Citizenship Act of 2004 .
The Andante with variations in F minor (Hoboken 17/6), also known as Un piccolo divertimento, was composed for piano by Joseph Haydn in 1793, and is among his most popular piano works.
 (The late British composer and pianist John McCabe, in his booklet note accompanying his boxed set of recordings of Haydn's complete solo keyboard music, was of the opinion that it was possibly inspired by the death of Maria Anna von Genzinger (1754-93, called "Marianne") [p. 23].
 McCabe also says that this piece is Haydn's "most extended and most resourceful such work for the keyboard" [p. 22].)
 The variations here are a set of double variations, the first theme is in F minor and the second theme in F major.
 Two variations of each theme and an extended coda follow.
The Variations on a Rococo Theme, Op. 33, for cello and orchestra was the closest Pyotr Ilyich Tchaikovsky ever came to writing a full concerto for cello and orchestra.
 The style was inspired by Mozart, Tchaikovsky's role model, and makes it clear that Tchaikovsky admired the Classical style very much.
 However, the "Theme" is not Rococo in origin, but actually an original theme in the Rococo style.
Brazilian nationality law is based on both the principles of "jus soli" and of "jus sanguinis".
 As a general rule, any person born in Brazil acquires Brazilian nationality at birth, irrespective of status of parents.
 Nationality law is regulated by Article 12 of the Brazilian Federal Constitution.
Anton Stepanovich Arensky (Russian: Анто́н Степа́нович Аре́нский ; 12 July [O.S. 30 June] 1861 – 25 February [O.S. 12 February] 1906 ), was a Russian composer of Romantic classical music, a pianist and a professor of music.
Multiple citizenship, also called dual citizenship or multiple nationality or dual nationality, is a person's citizenship status, in which a person is concurrently regarded as a citizen of more than one state under the laws of those states.
 There is no international convention which determines the nationality or citizen status of a person, which is defined exclusively by national laws, which vary and can be inconsistent with each other.
 Multiple citizenship arises because different countries use different, and not necessarily mutually exclusive, criteria for citizenship.
 Colloquial speech refers to people "holding" multiple citizenship but technically each nation makes a claim that this person be considered its national.
Variations on a Theme by Tchaikovsky, Op. 35a, a piece for string orchestra by Anton Arensky, started out as the slow movement of his String Quartet No. 2 in A minor, Op. 35, for the unusual scoring of violin, viola, and 2 cellos.
 It was written in 1894, the year after the death of Pyotr Ilyich Tchaikovsky, in a tribute to that composer.
 It was based on the theme from the song "Legend: Christ in His Garden", the fifth of "Sixteen Children’s Songs", Op. 54.
The Variations on a Theme by Joseph Haydn, (German: "Variationen über ein Thema von Jos. Haydn" ), now also called the Saint Anthony Variations, is a work in the form of a theme and variations, composed by Johannes Brahms in the summer of 1873 at Tutzing in Bavaria.
 It consists of a theme in B♭ major based on a "Chorale St Antoni", eight variations, and a finale.
 The work was published in two versions: for two pianos, written first but designated Op. 56b; and for orchestra, designated Op. 56a.
Nationality is a legal relationship between an individual person and a state.
 Nationality affords the state jurisdiction over the person and affords the person the protection of the state.
 What these rights and duties are vary from state to state.
Cornelius Lyons (c. 1670 - c. 1740) was an Irish harper and composer of harp tunes.
 He was the harper of the Earl of Antrim.
 Donnchadh Ó hAmhsaigh, known in English as Denis Hempson also a harper, was a great admirer of Cornelius Lyons and played a number of fine baroque-style variation sets by Lyons.
 Only one of the tunes Lyons composed survives; this is "Miss Hamilton" (Inion i Hamilton).
 However Lyons wrote variations on existing tunes of which five have survived, including "The Coolin" and "Slieve Gallen".
 "Miss Hamilton" was written in 1706.