Question:
The Macedonians (Greek: Makedones, Makedones) were an ancient tribe that lived on the alluvial plain around the rivers Haliacmon and lower Axios in the northeastern part of mainland Greece. Essentially an ancient Greek people, they gradually expanded from their homeland along the Haliacmon valley on the northern edge of the Greek world, absorbing or driving out neighbouring non-Greek tribes, primarily Thracian and Illyrian. They spoke Ancient Macedonian, a language closely related to Ancient Greek, perhaps a dialect, although the prestige language of the region was at first Attic and then Koine Greek. Their religious beliefs mirrored those of other Greeks, following the main deities of the Greek pantheon, although the Macedonians continued Archaic burial practices that had ceased in other parts of Greece after the 6th century BC.
Both Strabo and Thucydides said that Emathia and Pieria were mostly occupied by Thracians (Pieres, Paeonians) and Bottiaeans, as well as some Illyrian and Epirote tribes. Herodotus states that the Bryges were cohabitants with the Macedonians before their mass migration to Anatolia. If a group of ethnically definable Macedonian tribes were living in the Pierian highlands prior to their expansion, the first conquest was of the Pierian piedmont and coastal plain, including Vergina. The tribes may have launched their expansion from a base near Mount Bermion, according to Herodotus. Thucydides describes the Macedonian expansion specifically as a process of conquest led by the Argeads:  But the country along the sea which is now called Macedonia, was first acquired and made a kingdom by Alexander [I], father of Perdiccas [II] and his forefathers, who were originally Temenidae from Argos. They defeated and expelled from Pieria the Pierians ... and also expelled the Bottiaeans from Bottiaea ... they acquired as well a narrow strip of Paeonia extending along the Axios river from the interior to Pella and the sea. Beyond the Axios they possess the territory as far as the Strymon called Mygdonia, having driven out the Edoni. Moreover, they expelled from the district now called Eordaea the Eordi ... The Macedonians also made themselves rulers of certain places ... namely Anthemus, Grestonia, and a large part of Macedonia proper.  Thucydides's account gives a geographical overview of Macedonian possessions at the time of Alexander I's rule. To reconstruct a chronology of the expansion by Alexander I's predecessors is more difficult, but generally, three stages have been proposed from Thucydides' reading. The initial and most important conquest was of Pieria and Bottiaea, including the locations of Pydna and Dium. The second stage consolidated rule in Pieria and Bottiaea, captured Methone and Pella, and extended rule over Eordaea and Almopia. According to Hammond, the third stage occurred after 550 BC, when the Macedonians gained control over Mygdonia, Edonis, lower Paeonia, Bisaltia and Crestonia. However, the second stage might have occurred as late as 520 BC; and the third stage probably did not occur until after 479 BC, when the Macedonians capitalized on the weakened Paeonian state after the Persian withdrawal from Macedon and the rest of their mainland European territories. Whatever the case, Thucydides' account of the Macedonian state describes its accumulated territorial extent by the rule of Perdiccas II, Alexander I's son. Hammond has said that the early stages of Macedonian expansion were militaristic, subduing or expunging populations from a large and varied area. Pastoralism and highland living could not support a very concentrated settlement density, forcing pastoralist tribes to search for more arable lowlands suitable for agriculture.
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Why did they do this?

Answer:
Pastoralism and highland living could not support a very concentrated settlement density,

Answer the question at the end by quoting:

Van Halen is an American hard rock band formed in Pasadena, California, in 1972. From 1974 until 1985, the band consisted of guitarist Eddie Van Halen, vocalist David Lee Roth, drummer Alex Van Halen, and bassist Michael Anthony. The band went on to become major stars, and by the early 1980s they were one of the most successful rock acts of the time. 1984 was their most successful album.
David Lee Roth called Eddie to discuss what tracks would be included on a planned Van Halen compilation (work on which had actually begun before Hagar's departure). They got along well, and Eddie invited him up to his house/studio. Shortly afterwards, Roth re-entered the studio with the band and producer Glen Ballard. Two songs from those sessions were added to the band's Greatest Hits album and released as singles to promote it.  In September, Van Halen was asked to present an award at the 1996 MTV Video Music Awards. They agreed, and on September 4, 1996, the four original members of Van Halen made their first public appearance together in over eleven years. This helped to bring the compilation to No. 1 on the U.S. album charts. However, unknown to Roth, Eddie and Alex were still auditioning other singers, including Mitch Malloy.  The band's appearance on the 1996 MTV Video Music Awards fueled reunion speculation. But several weeks after the awards show, it was discovered that Roth was out of Van Halen again. Roth released a statement in which he apologized to the media and the fans, stating that he was an unwitting participant in a publicity stunt by Van Halen and manager Ray Danniels. The next day, Eddie and Alex released their own statement, claiming they had been completely honest with Roth and had never suggested he was guaranteed to be the next lead singer.  Eddie Van Halen would later explain (in regard to the MTV Video Music Awards appearance) that he had initially been embarrassed by Roth's antics while on camera behind Beck, who was giving an acceptance speech for the award that Van Halen had presented to him. Immediately following this, the band had been taken to a backstage press conference where press queries about a reunion tour were met with Eddie Van Halen saying that he needed a hip replacement and would have to record an entire new studio album before any tour. In private Roth told Eddie to avoid talking about negative things like his hip and the two almost came to blows, thereby shattering any chance of a full-scale reunion.

Was his return short lived?
Eddie Van Halen would later explain (in regard to the MTV Video Music Awards appearance) that he had initially been embarrassed by Roth's antics